It’s highly unusual for a high-ranking soldier, let alone a high-ranking Marine, to publicly question White House and Pentagon policy. Yet that’s exactly what four-star Gen. James Amos, Commandant of the Marine Corps, did yesterday in Washington.

Speaking at the Brookings Institute Tuesday, Amos said the Obama administration paved the way for the emergence of the Islamic State of Syria and Iraq (ISIS) by completely withdrawing American troops in 2011.

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“I have a hard time believing that had we been there, and worked with the government, and worked with parliament, and worked with the minister of defense, the minister of interior, I don't think we'd be in the same shape we're in today,” Amos said.

Amos also blasted the White House for failing to live up to its obligations around the world.

“We may think we're done with all of these nasty, thorny, tacky little things that are going on around the world -- and I'd argue that if you're in that nation, it's not a tacky, little thing for you. We may think we're done with them, but they're not done with us," Amos said.

“We're probably the only country in the world that has the resources and the capability to be able to do some of this that others can't,” Amos added.

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Perhaps Amos felt free to voice opinions on White House policy because he is set to retire this fall. Now, his comments are likely to influence the debate within the defense community about how to handle the myriad of crises going on around the world.

Unlike most issues in Washington, the argument surrounding American engagement around the world does not split along party lines. One strand of the GOP, represented by Rick Perry, believes the United States cannot retreat into an isolationist posture. The other, represented by Rand Paul, believes engagement will lead to prolonged wars like the one in Afghanistan.

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Amos is clearly in Perry’s camp. He also gave voice to a growing concern among DOD brass: that the troops who sacrificed by fighting in Iraq and Afghanistan are becoming disillusioned as the gains they made disappeared.

“It breaks our hearts,” Amos said, referring to the fall of the Anbar province in Iraq, which Marines won in 2010. He noted that 852 Marines were killed and another 8,500 injured in Iraq.

“They believed that they'd made a difference,” he said.

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