This story has been updated.
NATO's top official acknowledged in an interview that Russia's annexation of Crimea had "established certain facts on the ground" that would be difficult to change and said the military alliance was increasingly concerned that Moscow might also invade eastern Ukraine.
In the interview, NATO Secretary General Anders Fogh Rasmussen told Foreign Policy that Russia's sudden conquest of Ukraine's Crimean peninsula was a "wake-up call" for the 28-member alliance, which had been established to counter potential Soviet aggression during the Cold War. Rasmussen said NATO was committed to protecting Poland and other Baltic members of the alliance from what he described as an increasingly aggressive and land-hungry Russian government.
Ukraine's fragile central government has announced plans to withdraw all of its remaining troops from Crimea, a clear indication that Kiev has come to reluctantly accept that it can do nothing to halt or reverse the region's absorption into Russia. NATO, Rasmussen said, was now worried that Russia was turning its gaze further eastward and potentially preparing to seize other portions of Ukraine.
"Our concern is that Russia won't stop here," Rasmussen said. "There is a clear risk that Russia will go beyond Crimea and the next goal will be the eastern provinces of Ukraine."
A Russian invasion of eastern Ukraine, he added, "would have severe consequences." He declined to say what those might include, though, and stressed that NATO hadn't begun discussing any military options and wanted to de-escalate tensions with Russia rather than continuing down a path that could lead to an armed confrontation with Moscow.
Rasmussen's remarks come during at an unsettling time for the United States, Britain, and NATO's other 26 members. It was just weeks ago that Russian President Vladimir Putin was welcoming tens of thousands of tourists to Sochi for the Winter Olympics. Today, Putin is at the center of a tense showdown with President Obama that has plunged U.S.-Russian relations to their lowest levels in decades.
"More or less we took for granted that the Cold War belonged to the past," Rasmussen said. "And while I'm not yet ready to call recent incidents a new Cold War, there are of course similarities that remind us of old-fashioned Cold War attitudes on the Russian side, and that is a matter of concern."
Russia's invasion of Crimea has also focused new attention on NATO itself. Senior officials from both the Bush and Obama administrations have privately questioned its relevance in recent years and blasted the alliance's European members for slashing defense spending and effectively turning the continent's security over to the United States. European NATO members, in turn, have worried aloud that Obama's stated goal of reducing U.S. defense spending and focusing more attention on Asia meant that the administration was not as firmly committed to the alliance as its predecessors had been.
Rasmussen said he was working to reassure Poland and other nervous Baltic members of the alliance, who share borders with Russia and wonder if they will be Putin's next targets. The NATO chief said the alliance was committed to the defense of all of its members and would take strong, though unspecified, steps to protect the countries in the event of a Russian invasion. The Pentagon recently announced plans to move a dozen F-16s to Poland, and two NATO surveillance planes have begun flying over Poland and Romania to help the two countries better monitor their airspace and borders. Many Poles, though, say that the West isn't doing remotely enough to deter Putin.
The NATO chief acknowledged that the current crisis was NATO's biggest challenge in decades and cut to the heart of why the alliance had been created in the first place. Rasmussen said that he hoped it would lead European countries to sharply boost their defense spending, which he said had fallen to levels so low that they threatened the alliance's future effectiveness.
"This is a wake-up call and also a wake-up call when it comes to defense spending," he said in the interview, noting that some European countries had slashed their spending by up to 40 percent. "If this trend continues, European allies will not be able to provide effective deterrence and collective defense. This trend must be reversed."
Rasmussen, a former prime minister of Denmark, said the current crisis was "surreal" for him on a personal level.
"I grew up in the shadow of the wall and the Iron Curtain, and in a way I couldn't believe that it could be changed," he said. "Then suddenly, almost overnight, everything changed."
Now, he warned, things were at risk of changing again, this time for the worse.
"It is a Russian attempt to redraw the map and I would call it a kind of Russian revisionism which is unacceptable," he said. "It's not an acceptable behavior in the 21st century."
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