"Russians have long range nuclear-armed ballistic missiles," Carter said. "We [the United States] have to upgrade those [North Pole] radars... to cue missile defenses so that our missile defense interceptors can intercept them in flight."
"That is [North Pole] one of the places that ballistic missiles would overfly if they were en route to the United States," Carter explained. "We have to... make them more sensitive so that they are able to detect threats earlier."
In addition to Russia, he noted, the United States needs modern radar systems to defend itself against any possible missile attacks launched by China and North Korea.
Comment: While the fact that some U.S. military technology has been allowed to fall into obsolescence is interesting, it's highly unlikely that Russia or China would attack the U.S. This is another case of Western leaders spreading fear of an attack on American soil. Russia's attempts to upgrade its military is in response to U.S. provocation, not the other way around.
Russia has recently boosted its military presence in the Arctic region and has pressed ahead with efforts to develop its territories.
On Monday, Russian Defense Minister Sergei Shoigu said that Russia would enhance its naval fighter and surface-to-air missile regiments in the Arctic by the end of 2015.
In July, the head of Russia's Air Force announced that a special Arctic version of the Pantsir-S defense system would be developed. The Pantsir-S is a short-to-medium range surface-to-air missile and anti-aircraft artillery weapons system.
Russia has also conducted multiple small and large scale military drills in the Arctic. US State Department spokesperson John Kirby told reporters on Monday that Russia's military activities in the Arctic have not destabilized the region.
".. it's highly unlikely that Russia or China would attack the U.S."
That is a serious misunderstanding of the current state of the nuclear nations' defensive postures. There are numerous scenarios in which any of Russia, the U.S., or China might launch all-out nuclear attacks on one another.
These scenarios have their roots in the develoment of Multiple Independent Re-entry Vehicle (MIRV) missile systems. Prior to their development a nuclear exchange was largely self-disarming. It took one missile and one nuclear warhead to take out one of an opponent's missiles before it could be launched. After the development of MIRVs the equation changed. One missile could take out ten or more of an opponent's missiles. This put the advantage in the hands of the nation to launch first. The first nation to launch can take out most of an opponent's force while expending little of its own, retaining most of its force for mop-up operations and nuclear extortion.
The development of MIRV technology led, in turn, to different defense postures. Pre-MIRV, a nuclear detonation had to be confirmed before launching retaliation. That wouldn't work in a MIRV world because most of the attacked nation's retaliatory force would be knocked out before it could be launched. That forced the adoption of "Launch on Warning" (LOW) posture. That is, a nation will launch a retaliation before any of the opponent's missiles hit the ground.
Since the advent of MIRVs and LOW the nuclear forces of the world are inherently unstable. By analogy, consider floating various things on smooth water. A pie plate has positive stability - if disturbed it tends to return to its usual floating position. A tennis ball has neutral stability - if disturbed from it's initial orientation it floats in a new position. A pencil floated on one end has negative stability - it needs almost no perturbation to find a new stable position different from the original position. It never stays floating on one end.
Imagine a few scenarios:
1) A first nation becomes convinced, through multiple sources, that a launch from an opponent second nation is imminent - whether right or wrong. That first nation knows that the only way to "win" (using the term loosely) is to beat the second nation to the punch, and initiate the first launch.
2) A first nation's multiple technical resources indicate, wrongly, that a second nation has launched a nuclear attack. That first nation, under LOW protocols, launches a real nuclear attack against the second nation. (There are several documented cases of war amazingly avoided in such situations.)
3) A technical glitch or a rogue commander causes the launch of one or several of a first nation's nuclear missiles against a second nation. The command structure of that first nation quickly realizes the error. They also know that the defensive systems of the second nation will within minutes detect the launch and, having being in LOW defensive posture, the second nation will launch a massive retaliation. The only option left for the first nation is to follow up the initial error with a full-scale strike against the second nation.
The nuclear forces of Russia, the U.S., and China are presently a pencil that everyone is trying to float on one end.