Lt. Col. Ralph Peters (Ret.) joined Bill O'Reilly on "The Factor" tonight to react to President Obama's lack of a "complete strategy" to combat ISIS and his decision to approve the deployment of up to 450 additional U.S. troops to Iraq.

"The president has decided to take advice from his civilian advisors with no military experience, rather than from serious military planners," Peters said.

"You cannot possibly defeat the Islamic State with these airstrikes controlled by lawyers," Peters said, adding that Obama is simply unwilling to accept a limited number of civilian casualties.

Peters also asserted that the estimates of ISIS having 30,000 combatants in Iraq in Syria are low, and the real number is more like 70,000.

Not only that, he said, but now they are a "real army," composed of experienced, motivated combat veterans.

"They're fighting a war, and we're sitting it out," O'Reilly stated.

Watch more from "The O'Reilly Factor" above.

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