The U.S. is refocusing its attention on the Pacific at a time when its NATO partners may need to depend more heavily on American maritime power, an American Enterprise Institute report says.

“The US must recognize that even with its navy declining in size, over time, it will comprise an increasing percentage of alliance striking power,” says the report, “NATO at Sea, Trends in Allied Naval Power,” released this week.

“Absent a crisis or a threat that manifests itself largely as a naval threat, Europe is unlikely to return to large, balanced fleets,” the report says. “With US armed forces increasingly focused on the Asia-Pacific region, there are growing concerns as to whether the navies of America’s continental allies are up to meeting the challenges arising from the general unrest on Europe’s eastern and southern maritime flanks.”

Despite NATO taking its name from the ocean that ties Canada and the U.S. to their European allies, for most of NATO’s history the alliance focused primarily on land power, the report notes.

“However, with continental Europe at peace, the drawdown in Afghanistan, the rise of general unrest in North Africa and the Levant, and the American intent to pivot toward Asia, questions are increasingly arising about the capabilities of NATO’s European navies to project power and sustain operations around their eastern and southern maritime flanks,” the report says.

“These questions have grown even more urgent in the wake of those same navies’ uneven performance in the 2011 military campaign against Muammar Gaddafi’s Libya,” the report says. “Examining the major navies of America’s European allies reveals a general desire, with the exception of Germany, to maintain a broad spectrum of naval capabilities, including carriers, submarines and surface combatants. But given the significant reduction in each country’s overall defense budget, procuring new, sophisticated naval platforms has come at the cost of rapidly shrinking fleet sizes, leaving some to wonder whether what is driving the decision to sustain a broad but thin naval fleet capability is as much national pride as it is alliance strategy.”

Particularly telling, the report says, is the recent NATO operation in Libya.

“NATO’s reliance on the United States from March to October 2011 to carry out the allied mission in Libya — despite President Obama’s admonition that the United States would not take the lead in the military operation — is the result of two distinct causes: NATO-wide underinvestment in military capability and a lack of political will on the part of uniquely capable countries,” the report says. “Capability is absent in some areas; in others, it is unevenly distributed. When key platforms were present and fielded, they were often numerically too few.”