Admiral Mike Mullen, Chairman of the Joint Chiefs of Staff, generated quite the buzz with his proclamation last week that, "The most significant threat to our national security is our debt."  The same could be said for the NATO alliance.

Mullen explained that "ability for our country to resource our military" will be "directly proportional" to the strength of the economy. Further, he noted that projections have the payments on interest on the national debt to reach $600 billion by 2012 — an amount equal to the entire Pentagon budget.

That the comments took off over the weekend demonstrates the power of repetition:  Mullen and his boss, Defense Secretary Robert Gates, have been saying exactly the same thing for weeks.  Their message is that the Pentagon has to do its part to rein in bloated spending, particularly in prioritizing for longer term needs.  Most notably, they’ve been arguing for  a need to shift away from expensive contractor support to organic capability.

Those issues are much less of a problem for the other militaries in the Alliance, which are already quite lean.   But the resource constraints that have come from the global recession are now leading countries who have long fallen short of their commitment to spend two percent of their GDP on defense to cut even deeper.  And that’s going to make it very difficult to sustain a modern military Alliance.

As Reuters Political Risk Correspondent Peter Apps pointed out last month, it’s only natural the European politicians will target defense over popular domestic programs.  Particularly during bad economic times, which cry out for strengthening the safety net and propping up businesses reeling from the downturn. 

But NATO Secretary General Anders Fogh Rasmussen warned that, with the United States already footing three-quarters of the defense spending bill, there is a very real danger that the European forces would face "an extreme technology gap."  The political upshot, he correctly observed,   was that "we might end up with a situation where the Americans find the Transatlantic relationship less relevant."

NATO has withstood six decades of twists and turns in external threats, economic fortune, and political will.   And predictions of the Alliance’s demise have been proven wrong so many times that we should be wary of making them.   

But the gap Rasmussen spoke of is real.  Even if the United States makes deep cuts in the defense budget in the face of the growing debt — and that’s by no means a sure thing, given the powerful lobbying abilities of the military industrial complex —  it will come out of excess capacity, not core assets.   The Europeans, meanwhile, are already underfunded.  

The best hope, as I noted in "European Defense Cuts: Look on the Bright Side," is that the cuts will force consolidation and integration among European militaries and thus minimize the damage.   We’re seeing some promise of that, as with today’s announcement that Britain and France will share aircraft carriers.    If that happens, much of the cost savings can come from efficiencies — eliminating unnecessary duplication of capabilities and infrastructure.

James Joyner is managing editor of the Atlantic Council. 

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