Obama: 'Only one option' against ISIS

There is "only one option" for addressing the international threat of Islamic State militants, President Barack Obama said Wednesday.

Obama said the U.S. must be prepared to push for the ultimate destruction of the group (also known as ISIS or ISIL). The president addressed the nation after sending legislation to Congress seeking authorization for the use of military force (AUMF) against the militants.

"With vile groups like this there is only one option," Obama said. "With our allies and partners we are going to degrade and ultimately destroy this terrorist group."

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The request, which the president formally submitted earlier in the day, would seek to legalize a campaign against the militant organization for up to three years.

"If left unchecked, ISIL will pose a threat beyond the Middle East, including to the United States homeland," wrote Obama in a letter to Congress accompanying his draft of AUMF legislation.

The president stressed that he was not asking for the authorization of another ground war in the region, but the U.S. military needs to be prepared for "unforeseen circumstances" in the fight against ISIS. He gave the example of intelligence suggesting militant leaders were gathering at one location, and so he would want to have authorization to send in special forces.

President Barack Obama
Kevin Lamarque | Reuters
President Barack Obama

"We need flexibility but we also have to be careful and deliberate," Obama said of the proposed campaign.

The military actions could include U.S. boots on the ground in limited capacities—including hostage rescue missions—the White House said. But Obama emphasized that the military forces now there largely serve in bases, and do not have a combat mission.

The president said his legislation would repeal the 2002 authorization of force for the invasion of Iraq, and sets a limit on this campaign's authorization for three years. "I do not believe America's interests are served by endless war or by remaining on a perpetual war footing," he said.

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Still, Obama said the resolution should not be seen as a timetable for mission completion, but rather that the issue should be revisited by Congress at the beginning of the next president's term.

The draft resolution cites ISIS' responsibility for the killing of American citizens—including the recent death of aid worker Kayla Mueller—as one of the justifications for use of force.

Obama said he was optimistic the resolution would receive bipartisan support, and that it could "grow even stronger with the thoughtful and dignified debate that this moment demands."

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Touting what is largely a stalemate in Iraq, a failed ISIS offensive in Syria and reports of militants' "sinking morale," Obama expressed confidence that the campaign would eventually eradicate the group.

"Our coalition is strong, our cause is just and our mission will succeed," the president said at the conclusion of his speech. "And long after the terrorists we face today are destroyed and forgotten, America will continue to stand free, and tall, and strong."