At least five current or former military leaders are now on the record cautioning President Obama against firmly declaring that the United States will not deploy ground troops to fight ISIS.

It started on Tuesday at a Senate hearing when Gen. Martin Dempsey, the chairman of the Joint Chiefs of Staff, raised the possibility of ground forces being necessary.

"To be clear, if we reach the point where I believe our advisers should accompany Iraqi troops on attacks against specific ISIL targets, I will recommend that to the President," Dempsey said.

A day later, President Obama spoke from Central Command in Tampa, reiterating that U.S. troops will not have a "combat mission" in Iraq and vowing that he will not  send U.S. forces to fight "another ground war in Iraq."

But the chorus from the military community has grown louder.

Former Defense Secretary Robert Gates told CBS, "They're not gonna be able to be successful against ISIS strictly from the air, or strictly depending on the Iraqi forces, or the Peshmerga, or the Sunni tribes acting on their own. So there will be boots on the ground if there's to be any hope of success in the strategy. I think that by continuing to repeat that, the president in effect traps himself."

Army Chief of Staff Gen. Ray Odierno said, "You've got to have ground forces that are capable of going after them and rooting them out."

Retired Marine Gen. James Mattis told lawmakers that President Obama should not be pulling U.S. ground forces "off the table," arguing that any international coalition must be confident that America's military is "all in."

Former CENTCOM commander Gen. Anthony Zinni has said U.S. troops will have to be on the ground in some capacity in order to defeat ISIS.

The Outnumbered panel discussed the latest developments, with Kirsten Powers arguing that Obama has now "boxed himself in" on the question of U.S. ground forces. She said the Iraq war was a "disaster" but advised the president to realize that this situation is different.

Powers noted a conversation she had with a few Iraqis about the threat from ISIS.

"One of them opposed the Iraq war and actually is a pacifist, but she said 'at this point, I don't know what else we can do the only people that can handle this are the Americans.' The Iraqi troops can't handle it. It doesn't matter how many people you send to train them. It doesn't matter how many people you send to advise them. It's not gonna work. They're just not up to the task," said Powers.

Then we heard more expert analysis from Fox News national security analyst KT McFarland on "Happening Now." She said she's never seen such a split between current and former military leaders and a U.S. president.

She pointed to numerous problems with the president's strategy to defeat ISIS, arguing "we haven't even found" the so-called moderate Syrian rebels who will be trained to fight ISIS.

McFarland questioned where the other non-U.S. "boots" are going to come from.

She argued that the U.S. may someday need Iran's help to defeat ISIS if there isn't going to be a large deployment of U.S. ground forces. McFarland noted that Iran will likely want more concessions on its nuclear program in exchange for help against ISIS.