Obama: Defeating ISIS will be "different" from Iraq, Afghanistan wars

President Obama will announce that the U.S. will lead a coalition to destroy Islamic militants in Iraq and Syria, according to advance speech excerpts released by the White House.

"With a new Iraqi government in place, and following consultations with allies abroad and Congress at home, I can announce that America will lead a broad coalition to roll back this terrorist threat. Our objective is clear: we will degrade, and ultimately destroy, ISIL through a comprehensive and sustained counter-terrorism strategy," the president will say in a speech at 9 p.m. EDT Wednesday evening.

At the same time, however, the president will ask Americans to understand that U.S. efforts to combat the Islamic State of Iraq and Syria (ISIS), also known as ISIL "will be different from the wars in Iraq and Afghanistan."

"It will not involve American combat troops fighting on foreign soil. This counter-terrorism campaign will be waged through a steady, relentless effort to take out ISIL wherever they exist using our air power and our support for partner forces on the ground," the president will say.

He plans to explain that this strategy of taking out terrorists who threaten the U.S. while supporting non-U.S. partners on the ground "is one that we have successfully pursued in Yemen and Somalia for years."

Mr. Obama's speech comes less than two weeks after he said "we don't have a strategy yet" for how to approach ISIS. Though he wouldn't preview specifics of the president's plan, White House Press Secretary Josh Earnest said Tuesday it will be "similar to some of the other counterterrorism missions that the president has ordered and have been successfully executed by the United States military and with the support and in conjunction with our allies around the world."

Last month, the president authorized targeted airstrikes against the militants as they swept toward northern Iraq, where American military, diplomats and civilians are stationed. The U.S. military now plans on gradually expanding its air campaign against ISIS, CBS News Pentagon correspondent David Martin reports, not only in Iraq but also Syria once targets are identified.

There will also be an increase in the number of American military personnel on the ground in Iraq, though the size of the increase is not clear. However, Mr. Obama has outright rejected putting U.S. combat troops on the ground to fight ISIS, saying it would be a "profound mistake."

The U.S. has conducted 154 airstrikes in support of Iraqi troops and Kurdish peshmerga forces battling ISIS since Aug. 8. The Pentagon released a statement Wednesday saying it had damaged or destroyed 212 ISIS "targets" in total. Military officials said they have also conducted two major humanitarian operations and assisted in a major resupply of Kurdish forces.

Mr. Obama is also seeking from Congress legal authorization to train Syrian rebels in neighboring countries, a last-minute request he hopes to add to an upcoming spending bill.

He personally called House Appropriations Committee Chairman Hal Rogers, R-Kentucky, Tuesday evening to ask him to add the authorization to the spending bill the GOP leadership was planning to put up for a vote Thursday. The vote was rescheduled to give lawmakers time to consider the request.

Democrats have indicated they support Mr. Obama's request and agree it should be a part of the spending bill Congress is working to pass. House Minority Leader Nancy Pelosi, D-California, said on her way to a classified briefing Wednesday that she hopes the House will include the authorization in the spending bill because it stands the best chance of passing quickly.

Senate Majority Leader Harry Reid, D-Nevada, said on the Senate floor Wednesday morning, "It's clear to me that we need to train and equip Syrian rebels and other groups in the Middle East that need some help."

Reid said that the president was seeking the necessary authority to train the rebels, and "we should give it to him. That's one way of helping to build an international coalition."

Earlier Wednesday, the majority leader asked for a "cautious" approach to conflict.

"The president knows how to destroy terrorists and their organization; Osama bin Laden is proof of that," he said. "So, let's give the president of the United States time to do this the right way."