WASHINGTON — The US Army's top general Wednesday said he disagrees with Republican presidential front-runner Donald Trump's suggestion that the US should seize the oil used to support the Islamic State group.

Asked to respond to Trump's assertion, in a recent TV interview, that as president he "would go in and take the oil" using US military might, Gen. Ray Odierno said he disagreed with Trump: "Right now I do, yes."

"Here's what I've learned over the last 10 years or so: There's limits to military power," Odierno said. "We can have an outcome, but again, the problem is sustainable outcomes. We've had outcomes but they've been short-term outcomes because we haven't looked at the political and economic side. You have to look at all three together, and if you don't do that, it's not going to solve the problem."

Odierno made the comments in a wide-ranging Pentagon press conference, his last before he retires this month.

Odierno did not rule out increased military action, saying the US would "have to look at putting troops on the ground" if the Islamic State planned an imminent attack on the US. Yet he said to end the Islamic State's quest to become a long-term influence in the Middle East, "you need the countries of the Middle East and those that surround the Middle East to be involved in the solution," Odierno said.

The administration's handling of the Iraq war and the emergence of ISIS has become an issue in the 2016 presidential race. Odierno, whose career was defined by the Iraq war, took several questions about US policy in the Mideast.

In his 39-year Army career, Odierno served in Iraq as a division commander and commander of coalition forces during the troop surge of 2007; was named senior commander there in 2008 before he was replaced in 2010; and served briefly as commander of Joint Forces Command. He was confirmed Army chief of staff in 2011.

Though Jeb Bush, the former governor of Florida and a presidential candidate, Jeb Bush was not mentioned by name, a reporter asked about a narrative Bush advanced a day earlier in public remarks: That the Obama administration, after a successful troop surge, abandoned Iraq to renewed sectarianism and the Islamic State.

Asked if he agreed with the narrative, Odierno said, "I don't think it's black and white, I think it's gray. I think the military operations we conducted provided an opportunity for us to be successful.

"I remind everybody that us leaving in 2011 was negotiated in 2008 by the Bush administration, and that was always the plan," Odierno said. "We said we would respect their sovereignty, and so that was always our plan."

"Here's what I've learned over the last 10 years or so: There's limits to military power." Gen. Raymond Odierno, retiring Army chief of staff.

Jeb Bush, in remarks on Tuesday, faulted the administration for "leaving not even a residual force that commanders and the Joint Chiefs knew was necessary?" He also said former Secretary of State Hillary Clinton, the front-runner for the Democratic presidential nomination, "stood by" as secretary of state as the situation in Iraq deteriorated.

"That premature withdrawal was the fatal error, creating the void that ISIS moved in to fill and that Iran has exploited to the full as well. ISIS grew while the United States disengaged from the Middle East and ignored the threat."

In 2008, Baghdad agreed to the pullout of US troops, with a fixed deadline in 2011. US officials pressed Iraqi leadership to extend the troop presence, but Iraqi officials would not agree to provide legal immunity for US troops.

While Odierno speculated that the presence of US troops might have bolstered Iraqi institutions and staved off the cronyism in the Iraqi military, which contributed to its deterioration, he did not want to say whether the US worked hard enough to secure a deal.

"I hesitate to say that because, frankly, I was not there," he said. "I was told there was an effort to do that, so I can't tell you it was a robust effort. I simply can't comment. If I was there I'd give you an honest answer."

Asked about securing legal protections for US troops, Odierno said he could not say whether the Iraqis could have been convinced to provide it. He said US troops could not stay in Iraq without it, both for their own sake and because the UN-sanctioned mandate to stay had run out.

"We would have been in violation of international law," he said.

Email: jgould@defensenews.com

Twitter: @reporterjoe

Joe Gould was the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He had previously served as Congress reporter.

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