"We shrink from our global responsibilities at our peril, as retrenchment brought about by short-sighted cuts could well lead to costlier and more tragic consequences later — indeed as they always have in the past.”

That’s how Defense Secretary Robert Gates concluded his presentation about why the Obama administration would cut $78 billion from the Pentagon’s five-year budget. Not the most effective sales pitch: After 30 minutes of explaining the need for relatively small near-term savings, in 15 seconds he made it clear that the long-term price was unacceptably large.

These reductions were direct orders from the White House. While Gates managed to limit the damage, perhaps by as much as $50 billion, this is simply a continuation of the pattern begun in 2009. Obama’s defense cuts will have a compound, long-term effect on the overall purchasing power of the military. We won’t know the total extent of this year’s cuts for some time, including whether the “two-year probation” given to the Marine version of the F-35 Joint Strike Fighter is simply a stay of execution. Nonetheless, the Obama years have seen more than $350 billion in weapons modernization alone eliminated from the defense budget.

The collective cuts have taken a huge toll on the military. Killing the Army’s Future Combat Systems program not only deprived the service of a new generation of ground combat vehicles — for the fifth time since the end of the Cold War — but threw a monkey wrench in an innovative plan to “network” the force (which means, roughly, bringing it from the age of the Atari to the age of the iPhone). The shrinking of the Navy to fewer than 280 ships means the smallest fleet since World War I, when it shared the ruling of the world’s waves with the British Royal Navy.

The “Age of American Air Power” of the 1990s crashed with the 2009 termination of the F-22 Raptor. The Raptor had been the ultimate don’t-even-think-about-it message to potential adversaries; indeed, reports recently surfaced that North Korean leader Kim Jong-Il hid underground for over a week last year when the U.S. was hosting exercises in the region out of fear of attack from an F-22. And with the fate of the short-take-off version of the F-35 uncertain and the killing of the Expeditionary Fighting Vehicle, the Marine Corps’s future as a “forcible-entry” amphibious force — that is, the Marines as they’ve existed since World War II — is in serious doubt. In sum, Donald Rumsfeld’s idea to “skip a generation” of weapons modernization is being realized.

But more shocking than the weapons cuts was Gates’s announcement that the active-duty strength of the Army and Marine Corps will be trimmed by 47,000. This is especially jarring in light of the simultaneous announcement of an additional “surge” of 1,400 Marines into Afghanistan this month. Indeed, if the post-9/11 wars have proved one thing, it is that the land forces of the United States are too small. The Bush administration refused to expand the Army and Marine Corps until the 2007 Iraq surge, arguing that by the time new units could be organized and trained, the fighting would be over. Obama seems determined to repeat the folly of strategy-by-end-strength, again limiting combat commanders’ choices by constraining the resources available. The troop cuts aren’t supposed to take effect until 2015 — by which time the president has promised to be “out” of Iraq and all but out of Afghanistan — but they will begin to shape recruiting and retention almost immediately. Gates once led the charge to “win the wars we’re in,” yet he works for a commander-in-chief who’s interested only in ending the war he’s in. Our armies were too small before 9/11. They’ve been too small to fight in Iraq and Afghanistan simultaneously — we have a “one surge at a time” force. Cutting land forces now can only make the “Long War” longer.

Some things have changed since 2009, however: There’s a Republican majority in the House of Representatives and a strengthened minority in the Senate. And these proposed defense cuts pose an early test of character for the House leadership in particular.

Rep. Paul Ryan, who will write the alternative Republican budget — without question the most important political document of 2011 — has it right. “Everybody wants to have a peace-dividend budget, but we’re not at peace,” he says. “You can’t have a peace-dividend budget when we have two wars.” Rep. “Buck” McKeon, chairman of the House Armed Services Committee, is committed to restoring conservative support for strong national defense, and he emerged from a briefing by Gates stating, “I will not stand idly by and watch the White House gut defense when Americans are deployed in harm’s way.”

But there will be a temptation, particularly for a party struggling to meet is campaign “Pledge to America” to cut $100 billion in domestic discretionary spending, to look on the defense cuts — which amount to about $17 to $18 billion in the next year alone — as too good to refuse. House Majority Leader Eric Cantor has repeatedly suggested that defense should be “on the table” in deficit-cutting talks, and the wheeler-dealer Senate minority leader, Mitch McConnell, appears to agree.

Further, the White House has wrapped the deal in a shiny package of budget gimmickry. The administration is proposing a 2012 budget of $553 billion, nominally an increase from last year’s budget — although a decrease in Pentagon purchasing power and substantially less than the $570 billion projected in the Obama 2011 request. And it will take courage for House Republicans to confront Gates and the Joint Chiefs of Staff chairman Adm. Mike Mullen.

Gates’s argument is that defense dollars are not “sacred.” That is true, but that is also to trivialize the fact that national defense is different — a qualitatively different obligation of government than providing social services, health care, “internal improvements,” or economic development. And there is a moral dimension to defense spending, especially when only a few do the fighting and dying for the many.

It is ironic that the White House chose to announce defense spending cuts just as the House, by its public reading of the U.S. Constitution, tried to call the federal government back to its first principles. If there was one thing the Framers understood, it was that security was the first priority of the national government. We shall see if Republicans still share that priority.

Thomas Donnelly is a resident fellow and director of the Center for Defense Studies at AEI. Mackenzie Eaglen is a research fellow for National Security Studies at the Heritage Foundation. Jamie Fly is executive director of the Foreign Policy Initiative.