For all the GOP's muscular talk on Iran and its pledges to increase military spending, there's one place those calls aren't quite resonating: Within the military. 

Whether it's war with Iran or intervention in Syria, GOP leaders like Mitch McConnell and John McCain and presidential candidates like Mitt Romney and Rick Santorum, have been experiencing push-back from the Pentagon and military veterans over commitments to another military engagement. 

Today, the military rebuffed an idea by Senator McCain and Lindsey Graham to launch airstrikes In Syria. Testifying before Congress, Army Gen. Martin Dempsey said a "long-term, sustained air campaign would pose a challenge because Syria's air defenses are five times more sophisticated than Libya's," adding further caution that the country's "chemical and biological weapons stockpile is 100 times larger than Libya's."

Hawkish proclamations with regard to Iran have also irritated the Pentagon, notes National Journal's Yochi Dreazen with a between-the-lines read of Defense Secretary Leon Panetta's address to AIPAC yesterday. “In this town, it’s easy to talk tough. Acting tough is a hell of a lot more important," Panetta said. Noting that the comment didn't appear in his prepared remarks, Dreazen says "his departure from the text -- and the language he chose to use -- was clearly intended to respond to the GOP candidates who have spent the spent the run-up to Super Tuesday bashing Obama for his handling of Iran.”
 

While Panetta may be more of a standard politician than a military leader, it appears the top brass has his back, given remarks by Dempsey on Iran earlier. “We think that it’s not prudent at this point to decide to attack Iran. I mean, that’s been our counsel to our allies, the Israelis, well known, well documented,” Dempsey told CNN's Fareed Zakaria. “I’m confident that [the Israelis] understand our concerns, that a strike at this time would be destabilizing and wouldn’t achieve their long-term objectives.” The quote drew fire from Newt Gingrich who said "I just cannot imagine why he would have said it." Romney followed that up in his speech to AIPAC saying “Israel does not need public lectures about how to weigh decisions of war and peace. It needs our support.”

Those positions could be affecting the candidates' standings with veterans. Today, new polling data from the Truman National Security Project finds that Romney has been underperforming in counties with sizable populations of veteran voters, reports National Defense. "In 18 of the 23 counties with a veteran population of 15 percent, Romney underperformed his statewide numbers by an average of 11 points" Michael Moschella, political director of the Truman Project, said. A West Point graduate named Terron Sims said veterans have a "firm bull detector" and "don’t believe that Romney’s policy positions on national security are realistic." 

“We don’t mind disagreeing with candidates,” said Jim Morin who served in Afghanistan and Iraq. But veterans are worried "that his platform is purely politics, rather than sound policy."

As for the top brass, it's not so much that the military is a pacifistic institution, far from it, but it's inherently risk-averse and increasingly budget-conscious, explains Democrat Lee Hamilton, director of the Center on Congress at Indiana University, in an interview with Politico's Josh Gerstein. “The military is often cautious about commitments of military power,” he said “They see the difficulty of this situation from a military standpoint, not only the attack itself but sustaining the attack over a period of days, if not weeks. … A very powerful factor here is what the Pentagon now calls persistent conflict or endless war. We have, in effect, been at war for 10 years, at least since 9/11.”