In his second full news conference of the year, Bush confronted growing doubts about his administration's military strategy in Iraq.

He acknowledged public concern, saying weeks of sectarian violence since the Feb. 22 attack on a Shia shrine in the Iraqi city of Samarra has been "horrific." Hundreds of Iraqis have been killed.

"The terrorists haven't given up. They're tough-minded. They like to kill," said Bush, who spoke days after the third anniversary of the start of the Iraq war. "There will be more tough fighting ahead."

He said he disagreed with comments made on the weekend by former Iraqi interim prime minister Ayad Allawi, who on Sunday told the British Broadcasting Corporation: "If this is not civil war, then God knows what civil war is."

Bush said the fact that the Iraqi army has not "busted up into sectarian divisions," and that top Iraqi religious and political leaders are calling for unity is proof that the country is not in a civil war.

"This is a chance the Iraqis had to fall apart and they didn't," he said.

Bush called on Iraqi political leaders to "put aside their differences and reach across sectarian lines" to form a unified government as quickly as possible.

Secular divisions have stalled attempts to form an Iraqi government since the Dec. 2005 national elections.

Bush defended the continuing American military presence in Iraq, saying he has a plan for victory.

"If I didn't believe we could succeed, I wouldn't be there. I wouldn't put those kids there," he said, responding to questions on when U.S. troops would be brought home.

Bush said he can't let Iraq become a place for terrorists to plan future attacks on the U.S.

"If we left too early, Iraq would become a place of instability, a place to plot, plan and attack," he said.

The U.S. president bristled when asked why he went into Iraq in the first place, saying he tried to address the threat in Iraq through diplomatic means.

"I didn't want war. To assume I wanted war is just flat wrong. No president wants war."

In his second full-blown news conference of the year, Bush sought to ease his political problems by addressing them directly.

"Nobody likes war. It creates a sense of uncertainty in the country," he said. "War creates trauma." He acknowledged that Republicans are worried about their political standing in November.

"There's a certain unease as you head into an election year," Bush told a wide-ranging news conference that lasted nearly an hour.

More than 2,300 Americans have died in three years of war in Iraq. Polls show the public's support of the war and Bush himself have dramatically declined in recent months, jeopardizing the political goodwill he carried out of the 2004 re-election victory.

"I'd say I'm spending that capital on the war," Bush quipped.

When asked about his failed Social Security plan, he simply said: "It didn't get done." But the president defiantly defended his warrantless eavesdropping program, and baited Democrats who suggest that he broke the law.

Calling a censure resolution "needless partisanship," Bush challenged Democrats to go into the November midterm elections in opposition to eavesdropping on suspected terrorists. "They ought to stand up and say, 'The tools we're using to protect the American people should not be used,'" Bush said.

The news conference marked a new push by Bush to confront doubts about his strategy in Iraq. A day earlier, he acknowledged to a sometimes skeptical audience that there was dwindling support for his Iraq policy and that he understood why people were disheartened.

"The terrorists haven't given up. They're tough-minded. They like to kill," he said Tuesday. "There will be more tough fighting ahead."

Later in the news conference, Bush was asked whether there would come a day when no U.S. forces are in Iraq.

"That, of course, is an objective. And that will be decided by future presidents and future governments of Iraq," he said.

Asked if that meant it won't happen on his watch, the president said, "You mean a complete withdrawal? That's a timetable. I can only tell you that I will make decisions on force levels based upon what the commanders on the ground say."

The president said he did not agree with former interim Iraqi Prime Minister Ayad Allawi, who told the British Broadcasting Corporation Sunday, "If this is not civil war, then God knows what civil war is."

Bush said others inside and outside Iraq think the nation has stopped short of civil war. "There are other voices coming out of Iraq, by the way, other than Mr. Allawi, who I know by the way - like. A good fellow."

"We all recognized that there is violence, that there is sectarian violence. But the way I look at the situation is, the Iraqis looked and decided not to go into civil war."

Nearly four out of five Americans, including 70 percent of Republicans, believe civil war will break out in Iraq, according to a recent AP-Ipsos poll.

Bush said he's confident of victory in Iraq. "I'm optimistic we'll succeed. If not, I'd pull our troops out," he said, warning that abandoning the nation would be a dangerous mistake.

"So failure in Iraq, which isn't going to happen, would send all kinds of terrible signals to an enemy that wants to hurt us and people who are desperate to change the condition in the broader Middle East," Bush said.

He said he agreed to U.S. talks with Iran to underscore his point that Tehran's attempts to spread sectarian violence or provide support to Iraqi insurgents was unacceptable to the United States.

His opening remarks were designed to steel Americans for more fighting in Iraq and put an optimistic spin on the state of the U.S. economy.

"Productivity is strong. Inflation is contained. Household net worth is at an all-time high," Bush said, crediting his administration's policies.

Comment: "Household net worth" in the US is at an all time high, and yet so is personal and public debt?!

On Iraq, Bush bristled at a suggestion that he had wanted to wage war against that country since early in his presidency.

"I didn't want war. To assume I wanted war is just flat wrong ... with all due respect," he told a reporter. "No president wants war." To those who say otherwise, "it's simply not true," Bush said.

Asked about former supporters who now oppose him and the war, Bush said he's trying to win them over by "talking realistically to people" about the war and its importance to the nation.

"I can understand how Americans are worried about whether or not we can win," Bush said, adding that most Americans want victory "but they're concerned about whether or not we can win."

Bush scoffed at a question suggesting he should reshuffle or shake up his White House staff to help raise his sagging poll standings. But he did hint that he might bring in an experienced Washington insider to work with a disgruntled Congress.

"I'm not going to announce it right now," Bush said, adding that he's satisfied with the staff he's surrounded himself with.

"I think we'll be here forever," the 19-year-old airman from Wilkes-Barre, Pa., told a visitor to his base.

The Iraqi people suspect the same. Strong majorities tell pollsters they'd like to see a timetable for U.S. troops to leave, but believe Washington plans to keep military bases in their country.

The question of America's future in Iraq looms larger as the U.S. military enters the fourth year of its war here, waged first to oust President Saddam Hussein, and now to crush an Iraqi insurgency.

Ibrahim al-Jaafari, interim prime minister, has said he opposes permanent foreign bases. A wide range of American opinion is against them as well. Such bases would be a "stupid" provocation, says Gen. Anthony Zinni, former U.S. Mideast commander and a critic of the original U.S. invasion.

But events, in explosive situations like Iraq's, can turn "no" into "maybe" and even "yes."

The Shiite Muslims, ascendant in Baghdad, might decide they need long-term U.S. protection against insurgent Sunni Muslims. Washington might take the political risks to gain a strategic edge - in its confrontation with next-door Iran, for example.

The U.S. ambassador to Iraq, Zalmay Khalilzad, and other U.S. officials disavow any desire for permanent bases. But long-term access, as at other U.S. bases abroad, is different from "permanent," and the official U.S. position is carefully worded.

Lt. Cmdr. Joe Carpenter, a Pentagon spokesman on international security, told The Associated Press it would be "inappropriate" to discuss future basing until a new Iraqi government is in place, expected in the coming weeks.

Less formally, U.S. Defense Secretary Donald Rumsfeld, asked about "permanent duty stations" by a Marine during an Iraq visit in December, allowed that it was "an interesting question." He said it would have to be raised by the incoming Baghdad government, if "they have an interest in our assisting them for some period over time."

In Washington, Iraq scholar Phebe Marr finds the language intriguing. "If they aren't planning for bases, they ought to say so," she said. "I would expect to hear 'No bases."'

Right now what is heard is the pouring of concrete.

In 2005-06, Washington has authorized or proposed almost $1 billion for U.S. military construction in Iraq, as American forces consolidate at Balad, known as Anaconda, and a handful of other installations, big bases under the old regime.

They have already pulled out of 34 of the 110 bases they were holding last March, said Maj. Lee English of the U.S. command's Base Working Group, planning the consolidation.

"The coalition forces are moving outside the cities while continuing to provide security support to the Iraqi security forces," English said.

The move away from cities, perhaps eventually accompanied by U.S. force reductions, will lower the profile of U.S. troops, frequent targets of roadside bombs on city streets. Officers at Al-Asad Air Base, 10 desert miles from the nearest town, say it hasn't been hit by insurgent mortar or rocket fire since October.

Al-Asad will become even more isolated. The proposed 2006 supplemental budget for Iraq operations would provide $7.4 million to extend the no-man's-land and build new security fencing around the base, which at 19 square miles is so large that many assigned there take the Yellow or Blue bus routes to get around the base, or buy bicycles at a PX jammed with customers.

The latest budget also allots $39 million for new airfield lighting, air traffic control systems and upgrades allowing al-Asad to plug into the Iraqi electricity grid - a typical sign of a long-term base.

At Tallil, besides the new $14 million dining facility, Ali Air Base is to get, for $22 million, a double perimeter security fence with high-tech gate controls, guard towers and a moat - in military parlance, a "vehicle entrapment ditch with berm."

Here at Balad, the former Iraqi air force academy 40 miles north of Baghdad, the two 12,000-foot runways have become the logistics hub for all U.S. military operations in Iraq, and major upgrades began last year.

Army engineers say 31,000 truckloads of sand and gravel fed nine concrete-mixing plants on Balad, as contractors laid a $16 million ramp to park the Air Force's huge C-5 cargo planes; an $18 million ramp for workhorse C-130 transports; and the vast, $28 million main helicopter ramp, the length of 13 football fields, filled with attack, transport and reconnaissance helicopters.

Turkish builders are pouring tons more concrete for a fourth ramp beside the runways, for medical-evacuation and other aircraft on alert. And $25 million was approved for other "pavement projects," from a special road for munitions trucks to a compound for special forces.

The chief Air Force engineer here, Lt. Col. Scott Hoover, is also overseeing two crucial projects to add to Balad's longevity: equipping the two runways with new permanent lighting, and replacing a weak 3,500-foot section of one runway.

Once that's fixed, "we're good for as long as we need to run it," Hoover said. Ten years? he was asked. "I'd say so."

Away from the flight lines, among traffic jams and freshly planted palms, life improves on 14-square-mile Balad for its estimated 25,000 personnel, including several thousand American and other civilians.

They've inherited an Olympic-sized pool and a chandeliered cinema from the Iraqis. They can order their favorite Baskin-Robbins flavor at ice cream counters in five dining halls, and cut-rate Fords, Chevys or Harley-Davidsons, for delivery at home, at a PX-run "dealership." On one recent evening, not far from a big 24-hour gym, airmen hustled up and down two full-length, lighted outdoor basketball courts as F-16 fighters thundered home overhead.

"Balad's a fantastic base," Brig. Gen. Frank Gorenc, the Air Force's tactical commander in Iraq, said in an interview at his headquarters here.

Could it host a long-term U.S. presence?

"Eventually it could," said Gorenc, commander of the 332nd Air Expeditionary Wing. "But there's no commitment to any of the bases we operate, until somebody tells me that."

In the counterinsurgency fight, Balad's central location enables strike aircraft to reach targets in minutes. And in the broader context of reinforcing the U.S. presence in the oil-rich Mideast, Iraq bases are preferable to aircraft carriers in the Persian Gulf, said a longtime defense analyst.

"Carriers don't have the punch," said Gordon Adams of Washington's George Washington University. "There's a huge advantage to land-based infrastructure. At the level of strategy it makes total sense to have Iraq bases."

A U.S. congressional study cited another, less discussed use for possible Iraq bases: to install anti-ballistic defenses in case Iran fires missiles.

American bases next door could either deter or provoke Iran, noted Paul D. Hughes, a key planner in the early U.S. occupation of Iraq.

Overall, however, this retired Army colonel says American troops are unwanted in the Middle East. With long-term bases in Iraq, "We'd be inviting trouble," Hughes said.

"It's a stupid idea and clearly politically unacceptable," Zinni, a former Central Command chief, said in a Washington interview. "It would damage our image in the region, where people would decide that this" - seizing bases - "was our original intent."

Among Iraqis, the subject is almost too sensitive to discuss.

"People don't like bases," veteran politician Adnan Pachachi, a member of the new Parliament, told the AP. "If bases are absolutely necessary, if there's a perceived threat ... but I don't think even Iran will be a threat."

If long-term basing is, indeed, on the horizon, "the politics back here and the politics in the region say, 'Don't announce it,"' Adams said in Washington. That's what's done elsewhere, as with the quiet U.S. basing of spy planes and other aircraft in the United Arab Emirates.

Army and Air Force engineers, with little notice, have worked to give U.S. commanders solid installations in Iraq, and to give policymakers options. From the start, in 2003, the first Army engineers rolling into Balad took the long view, laying out a 10-year plan envisioning a move from tents to today's living quarters in air-conditioned trailers, to concrete-and-brick barracks by 2008.

In early 2006, no one's confirming such next steps, but a Balad "master plan," details undisclosed, is nearing completion, a possible model for al-Asad, Tallil and a fourth major base, al-Qayyarah in Iraq's north.

But Bush, who leaves office in January 2009, used a wide-ranging press conference to assure a US public unhappy with the war effort that he would call US troops home if he thought victory was impossible.

Asked whether all US forces would someday come home, the embattled US president said: "That, of course, is an objective. And that will be decided by future presidents and future governments of Iraq."

Bush also hinted at rifts in the diplomatic approach to
Iran's nuclear program, saying that Britain, France, Germany, Russia, China and the United States would meet later this week "to make sure that the message remains unified and concerted."

"It's important for our citizens to understand that we've got to deal with this issue diplomatically now," he said. "If the Iranians were to have a nuclear weapon, they could blackmail the world."

Russia and China, both veto-wielding permanent UN Security Council members, have resisted calls for the council to pressure Iran over its nuclear power program. Tehran denies US charges it secretly seeks atomic weapons.

Bush also said that the United States would make clear, in any talks with Iran about the situation in Iraq, that Washington viewed efforts to stoke sectarian violence and help arm insurgents as "unacceptable."

"This is a way for us to make it clear to them about what's right or wrong in their activities inside of Iraq," said the president, who denied that the strife-torn country had slipped into civil war.

"There's going to be more tough fighting ahead," he said, but "the Iraqis took a look and decided not to go to civil war" after the attack on a revered Shiite Muslim shrine.

"I'm optimistic we'll succeed. If not, I'd pull our troops out. If I didn't believe we had a plan for victory, I wouldn't leave our people in harm's way," he said. "I wouldn't put those kids there."

Some 2,300 US soldiers have been killed and many more wounded since the war in Iraq began almost exactly three years ago, and the open-ended conflict has dragged Bush's poll numbers to some of their lowest levels ever.

In the latest violence the commander of an Iraqi public order battalion and three other soldiers were killed Wednesday when rebels mortared their base south of Baghdad, an interior ministry official said.

Fourteen shells rained down on the barracks of the Al Salam brigade in Madain, about 20 kilometres (12 miles) south of the capital, in a pre-dawn attack on Wednesday. Three soldiers were also wounded.

Not far away, in the town of Latifiyah, 40 kilometres (24 miles) south of Baghdad, a joint US-Iraqi patrol clashed with insurgents also on Wednesday morning, killing one and detaining 11 suspects.

Bush's press conference came as some in his Republican party have worried that his unpopularity may drag down their prospects to retain control over the US Senate and House of Representatives in November mid-term elections.

For the second straight day, Bush took on critics who say his sunny forecasts for Iraq are out of touch with the bloody daily reality, insisting he was "realistic" and warning against a hasty US withdrawal.

And for what may have been the first time, the president said he knew things in Iraq were difficult because "I hear it from our troops" -- not only the media he has accused of focusing on violence rather than progress.

Bush, who has repeatedly said that US soldiers will come home only as Iraq's fledgling security forces can replace them, warned that a hasty withdrawal would embolden terrorists and discourage reformers in the Muslim world.

"If people in Iran, for example, who desire to have an Iranian-style democracy, Iranian-style freedom, if they see us lose our nerve, it's likely to undermine their boldness and their desire," he said.

"A democracy in Iraq is going to affect the neighborhood. A democracy in Iraq is going to inspire reformers in a part of the world that is desperate for reformation," he said.

Amid mounting calls for a staff shake up at the White House, the president also rejected calls for Defense Secretary Donald Rumsfeld's removal, saying "I don't believe he should resign. I think he's done a fine job."

But Bush suggested that he might make a change, saying: "I'm not going to announce it right now."

He had faced the stiffest potential sentence of any soldier charged so far in the Abu Ghraib scandal - up to 24 1/2 years in prison if convicted on all counts. The court planned an afternoon sentencing hearing.

The military jury deliberated for about 18 hours over three days before announcing its verdict.

The government contended that Smith, of the 523rd Military Police Detachment, Fort Riley, Kan., used his black Belgian shepherd to intimidate five prisoners for fun and competed with another canine handler trying to make detainees soil themselves.

The prison, which currently holds more than 4,500 detainees, came to symbolize American mishandling of some prisoners captured in Iraq, both during the U.S.-led invasion three years ago and in the fight to subdue the largely Sunni Muslim insurgency since then.

Widely publicized photographs of prisoner abuse by American military guards and interrogators at the led to intense global criticism of the U.S. war in Iraq and fueled the insurgency.

Earlier this month, the American military said that its new lockup near the Baghdad airport to house security prisoners now held at the notorious Abu Ghraib prison should be ready within three months, at which time it would close Abu Ghraib and turn it back over to the Iraqis.

In closing arguments Friday, a prosecutor said Smith had violated two tenets of his training: treat prisoners humanely and use the minimum amount of force needed to ensure compliance.

The defense argued that Smith was a good soldier who had done what he was supposed to do by having his dog bark at prisoners in a dangerous, chaotic environment where policies were so fuzzy that even the general who supervised interrogations testified he felt confused.

Smith, from Fort Lauderdale, Fla., was charged under the Uniform Code of Military Justice with five counts of maltreatment of detainees, four counts of assault, two counts of conspiracy to maltreat detainees, one count of dereliction of duty and one count of indecency.

The other dog handler, Sgt. Santos A. Cardona, 31, of Fullerton, Calif., is to stand trial May 22.

Nine other soldiers have been convicted of abusing detainees at Abu Ghraib. Among them, former Cpl. Charles Graner Jr. received the stiffest sentence - 10 years in prison.

(© 2006 The Associated Press.

The parties led by Massoud Barzani and Jalal Talabani function almost as a police state and views that, "Instead of one big Saddam, we have a hundred small Saddams in Kurdistan," Time reported.

Access to education, jobs and career advancement is often determined by party affiliation and there is no independent media in the region, Time wrote.

The weekly news magazine handled the problems in northern Iraq in the story titled "Trouble in Kurdistan." The frustration at this "dual monopoly" appear to have been behind a violent outburst last week at Halabja, the town on which Saddam Hussein inflicted a barbaric chemical attack in 1988, killing 5,000 people.

Time defended Kurdistan is a veritable police state, where the Asayeesh, the military security, has a house in each neighborhood, and where the Parastin "secret police" monitor phone conversations and keep tabs on who attends Friday prayers.

While these security measures are intended to prevent resistance cells from forming within its borders, they are often used by the ruling parties as an excuse to crack down on independent civil organizations. "Our members are regularly thrown into jail for seven or eight months at a time without cause. When they get out I tell them that they are lucky to be alive and to keep quiet," said Hadi Ali, the Minister of Justice, the token Kurdistan Islamic Union minister in the KDP-dominated Erbil administration.

According to the Minister of Justice, the courts in the region are almost completely politicized, with judges often rubber-stamping party decisions.

Hadi Ali said the secret police even have their own judges and during the last three Iraqi elections, schools, hospitals and other government buildings displayed portraits of the respective party leaders.

Access to education, jobs and career advancement is often determined by party affiliation. "The presidents of universities, the university council, deans and heads of the departments should all be members of one of the main parties, KDP or PUK," said Rebwar Ali, head of the Kurdistan Student's Development Organization.

Ali also stressed that admissions are not based on merit, but on membership to one of the two parties. Ali also asserted that student scholarships are only available for party members. Big business contracts depend on connections and political affiliations as well, leading to a pandemic of corruption, according to local businessmen.

'There are hundreds of Saddams in Kurdistan'

Demonstrations that are not supported by parties are outlawed, told Time Magazine, highlighting the small-scale parties constituting local coalitions.

The magazine asserted that these parties are bought or formed by the two major parties to create an image that these parties have wide public support and share in the administration.

Though religious marginal groups are treated with tolerance, these two parties use the Foundations Ministry to keep Muslims under strict control, Time noted. Although outlawed in 2003 by the Iraqi constitution, the Ministry, established by the British in the 1920s to control Muslims and later utilized by Baath officials, is still regarded as a source of pressure on the Kurdistan region, Time underlined. "We have hundreds of Saddams in Kurdistan instead of just one big Saddam," said Ahmad Vahab, head imam at Erbil Mosque, and a Kurdistan Iraqi Union deputy in the Iraqi parliament.

While emphasizing the news media in and around Kurdistan, Time referred to the absence of private satellite channels as an important factor for media to be run as the perfect tool for party propaganda.

The region is not suitable for a free news media at all, and some small-scale radio stations can only survive with financial support from the United States.

Kemal Said Kadir, a journalist and a professor of law, was sentenced to 30 years imprisonment when he was arrested for criticizing Barzani and his family in one of his articles.

Time evaluated the imprisonment of Mr. Kadir as an example of the politicization of courts as well as freedom of expression.

It ended in 2004, when US experts, after an exhaustive investigation, concluded that the men in those meetings were telling the truth, that Iraq had eliminated its weapons of mass destruction long ago, a finding that discredited the Bush administration's stated rationale for invading Iraq in 2003 – to find WMD.

The documents are among US government translations of audiotapes or Arabic-language transcripts from top-level Iraqi meetings – dating from around 1996-97 back to the period soon after the 1991 Gulf War, when the UN Security Council sent inspectors to disarm Iraq.

Even as the documents make clear that Saddam's regime had given up banned weapons, they also attest to its continued secretiveness: A 1997 document from Iraqi intelligence instructed agencies to keep confidential files away from UN teams, and to remove "any forbidden equipment".

Since it is now acknowledged the Iraqis had ended the arms programmes by then, the directive may have been aimed at securing stray pieces of equipment, and preserving some secrets from Iraq's 1980s work on chemical, biological and nuclear weapons.

Saddam's inner circle entertained notions of reviving the programmes some day, the documents show.

"The factories will remain in our brains," one unidentified participant told Saddam at a meeting, apparently in the early 1990s.

At the same meeting, however, the ex-president, who is now on trial for crimes against humanity, led a discussion about converting chemical-weapons factories to beneficial uses.

When a subordinate complained that UN inspectors had seized equipment at the plants useful for pharmaceutical and insecticide production, Saddam jumped in, saying they had "no right" to deny the Iraqis the equipment, since "they have ascertained that we have no intention to produce in this field (chemical weapons)".

The dozen transcribed discussions about weapons inspections largely dealt with Iraq'sdiplomatic strategies for getting the Security Council to confirm it had disarmed.

Scores of Iraqi documents, seized after the 2003 invasion, are being released at the request of the US House Intelligence Committee chairman, Representative Peter Hoekstra (Republican, Michigan), who has suggested that evidence might turn up that the Iraqis hid their weapons or sent them to neighbouring Syria. No such evidence has emerged.

Repeatedly in the transcripts, Saddam and his lieutenants remind each other that Iraq destroyed its chemical and biological weapons in the early 1990s, and shut down those programmes and the nuclear-bomb programme, which had never produced a weapon.

"We played by the rules of the game," Deputy Prime Minister Tariq Aziz said at a session in the mid-1990s.

"In 1991, our weapons were destroyed."

Amer Mohammed Rashid, a top weapons programme official, told a 1996 presidential meeting he laid out the facts to the UN chief inspector.

"We don't have anything to hide, so we're giving you all the details," he said he told Rolf Ekeus.

In his final report in October 2004, Charles Duelfer, head of a post-invasion US team of weapons hunters, concluded that Iraq and the UN inspectors had, indeed, dismantled the nuclear programme and destroyed the chemical and biological weapons stockpiles by 1992, and the Iraqis never resumed production.

Saddam's goal in the 1990s was to have the Security Council lift the economic sanctions strangling the Iraqi economy, by convincing council members that Iraq had eliminated its WMD. But he was thwarted at every turn by what he and aides viewed as US hard-liners blocking council action.

The inspectors "destroyed everything and said, 'Iraq completed 95% of their commitment'," Saddam said at one meeting.

"We co-operated with the resolutions 100 per cent and you all know that, and the 5% they claim we have not executed could take them 10 years to (verify).

"Don't think for a minute that we still have WMD," he told his deputies. "We have nothing."

"In the Iraq War, Rumsfeld and Franks dominated the planning," wrote the authors, Michael Gordon, military reporter for the New York Times, and retired general Bernard Trainor.

Vice President Dick Cheney "had the authority to serve as a counterweight to the Pentagon's optimism on postwar planning. But the vice president never once challenged the realism of Rumsfeld's expectations," they wrote.

According to the book, which was released to coincide with the third anniversary of the US-led invasion of Iraq, both Rumsfeld and Franks failed to recognize signs of a coming insurrection.

"There were indications from the first days of the invasion of the insurgency and guerrilla tactics to come, but they were ignored at the highest levels in Washington and at the Central command," it said.

Citing classified documents and interviews with US military officers on the ground in Iraq, the two authors sharply criticize Rumsfeld and Franks for faulty assumptions about how the war would unfold and how many troops would be required after the 2003 invasion.

"Just as Rumsfeld and Franks failed to understand the enemy, they also did not understand the actual structure of political power in Iraq. Rumsfeld and Franks believed that their victory would be sealed with the seizing of Baghdad, which was identified as Iraq's 'center of gravity'.

"But from the first day of the invasion the United States was not fighting a purely conventional war, one that would be suddenly brought to an end when the regime's ministries were seized and its leader toppled," the authors wrote.

Rumsfeld had placed too much confidence in US military technology and special operations forces while underestimating how many troops would be needed to occupy the country after toppling Saddam Hussein's regime, they said.

"Yet Rumsfeld was so confident of the validity of the prewar plan that he questioned the need to deploy the 1st Cavalry before Baghdad fell," they wrote.

"Just a week after Baghdad was seized, the White House, Defense Department, and CENTCOM (Central Command) were focused on withdrawing troops and replacing them with less-capable foreign troops instead of deploying the assets that would be needed to hedge against new threats," the book said.

The third anniversary of the US-led invasion has prompted a flood of criticism of the US administration's management of the war, including a commentary from a retired army general who was in charge of training Iraqi security forces in 2003 and 2004.

Retired major general Paul Eaton laid the blame for failures in Iraq on Rumsfeld, portraying him as a bullying micromanager who alienated allies and ignored military advice.

"In sum, he has shown himself incompetent strategically, operationally and tactically, and is far more than anyone else responsible for what has happened to our important mission in Iraq," he wrote in the New York Times on Sunday.

"Mr. Rumsfeld must step down," Eaton said.