The Center for Arms Control and Non-Proliferation has released study that's worth of a (scrupulous) look. Here's its central tenet:

In 2008, the most recent year for which complete global data is available, the U.S. approved $696.3 billion in defense budget authority (fiscal 2010 dollars). This figure includes funding for the Pentagon base budget, Department of Energy-administered nuclear weapons activities, and supplemental appropriations for Iraq and Afghanistan.

This number is eight times more than Russia, 15 times more than Japan, 47 times more than Israel, and nearly 73 times more than Iran.

In inflation-adjusted dollars, the total U.S. defense budget has grown from $432 billion in fiscal 2001 to $720 billion in fiscal 2011, a real increase of approximately 67 percent. The Congressional Budget Office has regularly warned that discretionary spending will come under increased pressure in the coming years. The legacy of the recent economic crisis will be a high and rising debt that must be addressed across the board.

None of the data here is in dispute, to the contrary, I think it's important to square these studies up factually and pragmatically. Like most of the metrics that advocates of disarmament use to further their political goals, wider analysis is noticeably absent. Why, for example, does America pump half a trillion annually in the defense budget? How are those forces used? Where do the dollars go (training, education, sustainment)? And who do we support and defend with our Armed Forces? The report doesn't even attempt to answer these questions.

Consider that:

1) America's defense budget is, first and foremost, an investment in global stability. Surely the South Koreans, Taiwanese, Israelis, members of the former Soviet bloc, and countless others concur in this assessment. Power, in magnanimous hands, is an anchor of peace.

2) As such, our forces are postured in such a way that discourages competition and aggression. Reagan sagely quipped that wars begin when governments believe that the cost of aggression is cheap, or "peace through superior firepower." When the Cold War fell, strategic planners correctly assessed that America's values of prosperity and liberty would be preserved and proliferated on the shoulders of a dominant, defensive military force. That tradition, which prevented a third world war with the Soviets, is fueled by our commitment to maintaining the world's most capable fighting force. It's not cheap, but a bargain if you treat the defense budget as an insurance policy.

3) While America does spend more on defense than the next several countries combined, this is more of a testament to its vast wealth than some sort of sinister imperial ambition. The United States's defense budget versus overall GDP is quite mild, ranking approximately 25th on the list, according to the CIA's World Factbook. Nor is our military the largest, ranking 8th in overall manpower.

4) The United States spends more on the average soldier than any other nation in the world. Our service members are the benefactors of the best education, health care, supplies, and pay for any military in the world. We do this for two reasons. We're an all volunteer force, and don't rely on conscription to fill military ranks like other nations. Certain incentives are required to sustain voluntary service, which drives up defense costs. Second, despite warfare's rapid technological advances in the past few decades, combat still requires talented soldiers who are educated, adequately resourced, and properly trained. As such, satisfying America's high standards for the average soldier, sailor, airman, or marine can be pricey.

5) How do we use our military? America is a benevolent power, primarily interested in the proliferation of stability, freedom, and prosperity. This should be a discriminating factor when comparing defense budgets to those of Russia, China, North Korea, etc, who often use their security services to maintain internal stability.

Last, and most important: We're currently embroiled in two wars -- while trying to preserve freedom of the seas (off the coast of Somalia, for example), support disaster relief efforts globally (like in Haiti and Indonesia), and deter powerful aggressor states from smaller allied nations. Never before in U.S. history have our soldiers been asked to do so much with so little, a strain which is in turn slowly atrophying the military.

Studies that simply compare the U.S. defense budget with the budgets of peer competitors make a poor case for slashing military defending. They don't factor in America's unique responsibility to world security and stability, nor are they part of the consideration in the nature and consistency of adversaries and allies alike. As Europe disarms and new potential competitors rise, the strategic demands shouldered by our military have grown exponentially since the end of the Cold War. We should fund our forces appropriately.

It's the prime directive for disarmament advocates to illustrate that America spends astronomically more on defense than the rest of the world, and then to wield that talking point into a larger, regimented political strategy. Spending less on defense frees up more for entitlement spending, so the argument goes, and it's perhaps an effective point with the largely liberal arms control community. But it misses the larger, more complex, picture.

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