President Barack Obama has unveiled his new budget, which proposes continued increases in military outlays. What for? The United States is spending far too much on the Pentagon.

There is no more important federal role than providing for the common defense. But what is required for defense depends upon circumstances. Military requirements in 1900 differed dramatically from those in 1940 and in 1980. What are the requirements today?

The latest Pentagon budget suggests that the United States is embattled and isolated, its territory threatened and its future imperiled. The Obama administration has proposed a $40 billion (8 percent) hike in military outlays in 2010 to $527.7 billion. (Counting Iraq and Afghanistan will push annual military spending up to around $700 billion.) President Obama plans to continue increasing the size of the Army and Marine Corps.

This proposal comes on top of a 75 percent increase in real military outlays under the Bush administration. Today, Washington possesses the world's most sophisticated nuclear arsenal, most powerful air force, most dominating navy and most effective army. America accounts for roughly half of global military outlays. Observes the Cato Institute's Ben Friedman: "Add the wars, nuclear weapons research, veterans, and homeland security, and you get about $750 billion. That is more than six times what China spends, 10 times what Russia spends and 70 times what Iran, North Korea and Syria spend combined."

Nevertheless, Pentagon officials and conservative activists are complaining about defense "cuts" since the new administration has reduced the Pentagon's request for even more money. Robert Kagan of the Carnegie Endowment for International Peace even contends that the Obama administration is signaling that "the American retreat has begun."

Thus, a mix of officials, lobbyists, and analysts advocate spending a fixed percentage of GDP on the military, irrespective of circumstance. Both Secretary of Defense Robert Gates and Joint Chiefs of Staff Chairman Admiral Mike Mullen advocate setting a spending floor of 4 percent of GDP. Marion Blakey, president of the Aerospace Industries Association says the 4 percent floor should be "front and center for any new president's agenda." Former Missouri Senator James Talent has been promoting the same number. The Heritage Foundation calls this the "4% for Freedom Solution." (Baseline spending currently runs 3.7 percent.)

Steven Kosiak of the Center for Strategic and Budgetary Assessments figures that a four percent rule would increase military outlays above current plans by between $1.4 and $1.7 trillion over the next decade. Even that isn't enough money for some uber-hawks. Republican presidential candidate Fred Thompson wanted 4.5 percent of GDP. AEI's Gary Schmitt prefers five percent. The Wall Street Journal has editorialized for five to six percent. Former and potential GOP presidential candidate Mike Huckabee advocated six percent-more than a 50 percent hike over today's levels.

Whatever could justify such increases?

The United States already spends more on the military in real terms than it did during the cold war, even as the very hot Korean and Vietnam Wars raged. America devotes a lower percentage of its GDP to the military, but the U.S. economy is much greater today-six times (adjusting for inflation) as big as at the end of World War II. Total resources for defense are higher today than at any other point in over six decades.

Nevertheless, worries Admiral Mullen: "the four percent floor is . . . really important, given the world we're living in, given the threats that we see out there, the risks that are, in fact, global, not just in the Middle East." Bret Stephens of the Wall Street Journal believes that we are in what amounts to a new post-Locarno world like that before World War II, as the forces of darkness were gathering. AEI's Frederick Kagan argued that "American inattention to the world in the coming years could lead to a similarly devastating result" like World War II, since "the current international environment is by any comparison more dangerous for the U.S. than the one that led to World War II." Jim Talent contended: "We live in a multipolar world with threats that are highly unpredictable and therefore, taken as a whole, more dangerous than the threats we faced during the cold war." Representative John Shadegg claimed that "Our nation is facing the threat of Radical Islam, the gravest threat to our national security in history."

If these claims are true, then why spend only four percent of GDP on defense? Why not 9.4 percent, as during the Vietnam War? Or 14.2 percent, as during the Korean War? Or 37.8 percent, as during World War II? Or even more? After all, we can never be too safe.

The reason why not is simple. These apocalyptic claims are absurd.

There is no longer a Nazi Germany or imperial Japan. Nor even a fascist Italy. There is no more Soviet Union or Warsaw Pact. There is no longer an ideologically-aggressive Communist China allied with the Soviet Union. The patchwork of Third World states backed by the Soviet Union has dissolved. As Gertrude Stein once said of Oakland, there is no there there in terms of traditional military threats.

At the same time, Washington spends almost as much as the rest of the world combined on our military. Sure, some small or poor states devote a larger percentage of their limited resources to defense, but their total outlays remain minuscule compared to those of America. That's not all, however. The United States is allied with every major industrialized state save China and Russia. America and other NATO members together account for about $1.05 trillion out of $1.470 trillion in world military expenditures. Adding Japan, South Korea, and Australia take the allied up to $1.15 trillion.

Nevertheless, when running for president Rudy Giuliani opined: "The idea of a post-Cold War 'peace dividend' was a serious mistake-the product of wishful thinking and the opposite of true realism." The Washington Examiner worries that "potential adversaries rapidly are ramping up their militaries."

Precisely who?

America's relationship with Moscow and Beijing is civil, if sometimes difficult. Even if one assumes greater hostility not today evident, the United States vastly outranges both militarily. America's defense expenditures-not counting spending for the Afghanistan and Iraq wars-run at least four times and as much as seven times as much as each of their outlays (for which estimates vary). America has eleven carrier groups, while Russia has one and China has none. Moscow has a nuclear force sufficient to deter U.S. military action, but little conventional capability beyond its own borders. Russia can beat up neighboring Georgia, but not threaten the United States.

Beijing is investing more in the military, but is starting with a far lower base and still spending far less. If the People's Republic of China (PRC) wants to overtake Washington as a global power, the PRC will have to spend more than America for years. What China is doing today is creating a defensive force capable of deterring U.S. intervention, not an offensive force capable of attacking America. And even as China grows economically, it will remain well behind the United States in wealth. America's per capita GDP last year was $48,000. That of China was $6,100. The PRC is in no position to match, let alone overtake, America, in the foreseeable future.

Moreover, Russia's and China's neighbors, most of whom are close friends of Washington, could do much more if necessary: America's allies account for about three-quarters of world GDP, and the number goes higher when one includes friendly states like India. The European Union's GDP alone is thirteen times as great as that of Russia.

Japan's economy remains roughly as large as that of the PRC (estimates differ). Still, China has a greater prospect than Russia of becoming regionally dominant. But Beijing is surrounded by countries with which it has fought wars: Russia, Japan, India and Vietnam. Further, India, Japan, South Korea, Australia and ASEAN states have created or could create militaries capable of deterring Chinese adventurism. Beijing would have to undertake a dramatic military build-up to overwhelm Washington's East Asian friends, let alone threaten America's territory.

Could circumstances change in five, ten or twenty years? Yes, but it makes no sense for the United States to waste money today dealing with unlikely scenarios which, even if they occurred, could be dealt with less expensively in the future. America will be stronger and better prepared to face future challenges if it husbands its resources and encourages economic growth today. The United States should work to defuse, not exacerbate conflict. For instance, philosophical distaste for Vladimir Putin's Russia is no reason to turn it into a military adversary.

If not China and Russia, then who threatens America? Washington has forged better ties with India and has no serious conflicts with other emerging powers, such as Brazil, Indonesia and South Africa. America's presumed enemies are few and pitiful: North Korea, Iran, Cuba. Maybe Burma and Venezuela. Toss in Sudan and Somalia, as if the latter actually existed as a nation. Stretch to include Syria. This disparate group is no replacement for the Axis alliance or Soviet empire.