The US president blazed a path to the White House on a platform that promised a complete break with George W Bush.

© ReutersA protester in Colombo, Sri Lanka rails against US military involvement in Libya, Iraq and Afghanistan
For the first time in a decade, the mainstream Republican consensus around war in the Middle East and western Asia is fractured. During a recent debate among candidates for the Republican Party's nomination for president, former Massachusetts state governor Mitt Romney declared that US troops ought to begin withdrawing from Afghanistan as soon as possible. That sentiment was echoed by several other debate participants. At the same time, US President Barack Obama appears to be incapable of ending any of America's ongoing wars. Therefore, one of several Republican presidential candidates may be preferable to the incumbent, at least among people who would like to see an end to US-led military adventures.

Barack Obama blazed a path to the White House on a platform that promised a complete break with the George W Bush presidency. On Guantanamo Bay, rendition, corporate accountability, finance reform, habeas corpus, illegal wiretapping, domestic spying, whistleblowers, Afghanistan - and a host of other issues - the current president promised change. In reality, however, he only offered continuity and in some cases, such as the prosecution of whistle blowers and the assassination of US citizens overseas, he outstripped his predecessor's zeal.

Many people who took Obama's campaign promises at face value were disappointed by the gaping chasm between his words and actions. The president famously derided liberals' credulity and purported naiveté at a $30,000-a-plate fundraising dinner; they expected too much change too quickly, he said. But as Glenn Greenwald noted recently, the main problem isn't that change is coming too slowly, it's that the president is "doing the opposite [of changing the dynamic]". Indeed, on most meaningful counts, this president has engineered the entrenchment and growth of the Bush-era security state and imperial presidency.

Yet, despite Obama's stellar establishmentarian credentials, he is regarded by his political opponents as a weak politician. A part of that perception is based on reality; on several occasions Obama has been roundly humiliated by Binyamin Netanyahu, the prime minister of Israel. But a part of that perception is also based in political myth-making. Across the US political and media spectrum, members of the Democratic Party are portrayed as vulnerable, particularly on security issues. And in a political culture which somehow continues to permit sexist caricatures, the Democrats are routinely portrayed as effeminate.

Never mind the fact that Obama escalated the war in Afghanistan. Forget also the fact that he ramped up the air-wars in Pakistan and Yemen - starting one in Libya - or presided over the killing of Osama bin Laden. When it comes to perceptions in the US, Obama is still a Democrat, and Democrats are still the weaker party on national security.

It is for that reason that that this president cannot be relied on to withdraw troops from Afghanistan. Nor can he be expected to end any military engagement (with the exception of Libya, which will likely end when Gaddafi is deposed or dead) while he remains in office.

US politicians, particularly the president, are forced to contend with a perpetual election cycle. For Democrats, that means a constant hyper-sensitivity to any policies that may be construed as weakening national security. Whether the policies are actually good or bad for America is beside the point; it's the perception that matters.

In the case of Afghanistan, an increasing number of US citizens agree that troop withdrawals are in the country's interest. But if the current president initiates a withdrawal, one of his many opportunistic opponents will employ the slogan: "Barack Obama abandoned Afghanistan to al-Qaeda" - or something like it - to likely great effect.

While Obama will not be eligible to run for president in 2016 (if he wins in 2012), he will campaign for his Democratic successor - which means that the vulnerability to "weak" sloganeering will continue to restrict his ability to manoeuvre.

A Republican president is not subject to the same perceptions. If a Mitt Romney or Ron Paul chose to end any of America's five overt or covert wars (Afghanistan; Iraq; Libya; Pakistan; Yemen), no Democrat can credibly accuse him of harming national security.

The conclusion is that if anti-war liberals hope to see a US withdrawal from Afghanistan before 2016, they are better off voting for the Republican candidate in 2012 - provided it is one of the candidates who voiced an interest in withdrawing - or at least withholding the vote from Obama.

To be sure, this is a very unlikely scenario. Part of the reason for that is that people on the left - like political partisans everywhere - usually have a very deep distrust of the other side, even when their own is adopting the same policies. Democratic strategists are aware of the left's aversion to Republican candidates and are counting on that sentiment to guide their president to victory. Alex Pareene humorously essentialises their arguments:

"A Republican president will most likely do what the last three Republican presidents have done: Starve the government of revenue, allow industries to capture regulators, launch pointless and bloody foreign misadventures, and threaten to gut the welfare state. I mean, all of those things might be happening now, with a Democrat, but they would happen so much worse with Mitt Romney, probably! So vote Obama again!"

Unfortunately, many people probably will vote for Obama again. And unfortunately, that vote will likely be for another five years of war.