The NATO meeting in Chicago this weekend is a chance for alliance leaders to proclaim solidarity and promise success. But the gathering probably won't resolve the underlying anxiety about sharing the burdens of defense, a concern heightened by Europe's economic crisis and America's growing weariness at carrying the heaviest load.
Drastic budget cuts in some European countries are exasperating tensions over a yawning gap in military capabilities between the United States and other NATO members. From NATO's birth in 1949 at the dawn of the Cold War, the U.S. has provided the bulk of the military might. That arrangement, however, is fraying in an age of austerity and in the absence of a Soviet-like invasion threat to compel more military spending by the Europeans.
"NATO needs a new bargain," says Barry Pavel, director of the international security program at the Atlantic Council, a think tank. "The time when Europeans can expect the U.S. to dominate operations in Europe or nearby without U.S. vital interests are over."
Worry in Europe and the U.S. about fractures in the alliance are nearly as old as NATO itself. In recent years, a more ambitious military agenda, including a formal NATO fighting role in Afghanistan, has created deeper divisions.
For example, the Europeans largely have viewed Afghanistan as a humanitarian, not combat, mission, and that explains why Washington for years had trouble getting Europeans to provide more forces.
Also, the U.S. invasion of Iraq in 2003 caused a deep rift with important European partners, including France and Germany, which publicly opposed the war.
Even as the alliance has expanded its reach outside of Europe, declining defense spending on both sides of the Atlantic, but particularly in Europe, is crimping NATO's capabilities and trying the U.S. willingness to take on every European security issue.
A case in point is Libya. The operation last year to ground Moammar Gadhafi's air force by imposing a "no fly zone" over the country was carried out under a NATO flag. But the mission probably could not have succeeded without the American military, which provided most of the firepower, especially in the riskiest early stages.
Ivo Daalder, the U.S. ambassador to NATO, has said the Libya mission "only accentuated" the growing gap in capabilities between the U.S. and its European partners, who actually ran short of precision-guided munitions at one point.
Daalder said the U.S. provided 75 percent of all intelligence, surveillance, and reconnaissance assets and flew 75 percent of aerial refueling missions in the Libya operation. It also provided the bulk of the officers who coordinated the targeting.
As part of the solution to the Europeans' lack of aerial surveillance capabilities, NATO agreed in February to buy a fleet of five U.S.-made unmanned Global Hawk high-altitude surveillance aircraft for about $1 billion. The U.S. is on the hook for about 40 percent of the tab. The drones are to operate out of an air base in Italy. This deal was a breakthrough for NATO, ending a 19-year debate over how to pay for it.
Throughout the Cold War, a military and political partnership with Western Europe was fundamental to U.S. defense policy. But in the two decades since the demise of the Soviet Union, the security landscape has been reshaped. For a growing number of Americans, NATO is an abstract and obscure relic.
That causes many in Congress to question why the U.S. should continue to pay the lion's share of defense costs. The U.S. defense budget of nearly $700 billion accounts for nearly three-quarters of the total defense spending by NATO members. The combined military spending of all 26 European members is just above $220 billion.
NATO long has set of goal for each of its 28 members to spend at least 2 percent of its gross domestic product on defense, but the only members consistently doing that over the past two decades are the U.S., Britain, France, Turkey and Greece, according to NATO statistics.
The recent economic turmoil in Europe, punctuated by the threat of bank failures, is making the gap worse and leading to more urgent questions about burden sharing. In one tangible example, the Netherlands announced last year that it would eliminate 1 in 6 of its military personnel and liquidate its entire tank arsenal.
The chairman of the House Armed Services Committee, Rep. Howard P. "Buck" McKeon, recently complained that for every dollar the U.S. is spending on homeland missile defense it is spending four times that much on regional missile defenses such as the one being erected in Europe.
"What's more, European missile defense will be a `national contribution' to NATO, meaning the cost will be borne entirely by the U.S. at a time when most of NATO is failing to meet even the 2 percent of GDP threshold," McKeon, R-Calif., said at a recent hearing.
The Chicago summit is expected to announce that a nascent NATO missile defense system has achieved an "interim," or startup capability, a milestone that in practice means it is mainly an American system. It is unlikely to be fully operational, with substantial European contributions, before the end of the decade.
The widening disconnect across the Atlantic prompted Robert Gates, in his final policy speech as U.S. defense secretary 11 months ago, to say that the alliance faced a "dim if not dismal" future. Speaking in Brussels, the city that hosts NATO headquarters, he said Europeans' penny-pinching and lack of political will could hasten the end of U.S. support for NATO.
A short time later he said he did not expect NATO to shatter but rather to slowly grow apart. "It's a troubled marriage," he told The Associated Press.
Since he took over from Gates last July as Pentagon chief, Leon Panetta has cast the alliance as central to U.S. defense strategy. Yet he also is cutting the number of U.S. Army brigades in Germany from three to one, while keeping one brigade in Italy and promising that rotational training missions in Europe by other Army units will keep the bonds tight.
The impression that the U.S. is losing interest in Europe was reinforced, however when the Obama administration declared last year that in the aftermath of U.S. wars in the Middle East it was "pivoting" to Asia as part of a shifting of strategic priorities. Administration officials are so concerned about this perception that they have started substituting the word "rebalancing" for "pivoting," to avoid the notion of turning away from Europe.
Annette Heuser, executive director of Germany's Bertelsmann Foundation in Washington, which focuses on trans-Atlantic cooperation, said in an interview that Europe is unmistakably anxious about U.S. intentions in Europe.
"NATO is the one and only institutional anchor that Europe has with the United States, and also the only way Europe can magnify its military power," Heuser said. "Without NATO, Europe could not play on the world stage as a security actor."