A coalition of conservative think tanks is gearing up to fend off calls for cuts to the Defense budget coming from both the left and right - and from Obama's Republican Defense Secretary Bob Gates as well.

A Wall Street Journal op-ed Monday by the Foreign Policy Initiative's William Kristol, the American Enterprise Institute's Arthur Brooks, and the Heritage Foundation's Edwin Feulner is the opening salvo of an initiative of the three think tanks called "defending defense."

Organizers of the initiative say they are preparing to "educate" the new Congress and issue a fact sheet Wednesday that argues that defense spending should be spared from federal budget cuts.

"We want to make clear that those concerned about spending levels should not jump to the conclusion that the defense budget is the place to make cuts, when in reality, it has very little to do with our current predicament," FPI's Jamie Fly told POLITICO Monday.

The coalition argues that spending on the Afghan and Iraq wars should not be included in examining the Defense Department's base budget which, they argue, is underfunded.

"The wars are expensive - absolutely," Heritage Foundation military analyst Mackenzie Eaglen told POLITICO Tuesday. "But the peace time budget - the base budget in the Pentagon - is hemorrhaging and underfunded. That's a hard message to sell in this environment."

Congressional appropriators from both parties, Eaglen emphasized, recently cut Obama's requested FY'11 defense budget by $7 billion to $710 billion. With some $130 billion of that slotted for the wars in Iraq and Afghanistan, that leaves $580 billion for the rest of the Defense Department.

The current and incoming Congress's focus on reducing federal spending as well as the President's deficit reduction commission report due out Dec. 1 contributed to bringing the coalition together now, Eaglen said.

The group is also concerned about Gates' emphasis on rationalizing the Pentagon budget.

"The Secretary's worldview has become the conventional wisdom," Eaglen, a former Hill defense staffer most recently for Sen. Susan Collins (R-Maine), said. "We want to offer an alternative narrative. He wants to win today at the expense of the future, and we believe we have to do both."

"From our perspective it's not just about weapons systems and procurement," said AEI's Tom Donnelly. "One of the things that worries me most is that reduction in defense budgets would be visited upon personnel and that the army we just barely grew by 10% since 9/11 would be reduced back again to its pre-9/11 levels and we would lose the small increases of the last seven or eight years."

"From a budget perspective, that's a highly likely target, which would be disastrous," Donnelly added. 

While the group focuses on perceived calls from the left to slow defense spending, the coalition doesn't dispute that its concern is also with the growing strength of the libertarian wing of the Republican party -- fiscal hawks over national security hawks, if you will.

"What's changing is that we can't take Republican support for military strength nearly for granted anymore," AEI's Donnelly said.

"A range of conservatives have publicly called for hemming in defense spending, including Sen. Tom Coburn (R-OK), former Sen. Alan Simpson (R-WY), Kentucky Senate candidate Rand Paul and prospective GOP presidential candidate Mitch Daniels," the progressive National Security Network wrote Tuesday.