Sen. John McCain (R-Ariz.) responded to President Obama's request to Congress for an authorization to use military force against ISIS in Iraq and Syria. 

Calling it "a study in Obama incoherence," the Senate Armed Services Committee chairman called out Obama for failing to clearly "articulate" the strategy. 

McCain said the "ugly truth" is that "we are going to have to have boots on the ground" because the Iraqi army, the Kurdish peshmerga and Iranian-backed Shia militias cannot be relied upon to defeat ISIS. 

"Any military man worth his salt, or a woman, will tell you that you have to have American forward air controllers, special forces and other capabilities embedded in these forces," said McCain.

"If he would come to Congress and say 'here's our strategy' instead of just announcing what we won't do, which is in his tradition of announcing withdrawals, there might be something to it," said McCain, calling Obama's plan a "tacit continuation of what has failed."

He was asked whether Iraqi and Syrian forces can achieve Obama's goal of defeating ISIS. 

McCain said "over time" and with enough training and equipment it could work, but said there would be missions "that only the United States can do."

He said the problems in the region go beyond ISIS, with Bashar Assad still in power in Syria and Iran getting stronger.

"The Iranian threat is now widespread, the latest being in Yemen, the Houthis being an Iranian-sponsored terrorist organization. We just have to keep pressing to get this president and this administration to recognize that there is a direct threat to the United States of America."

Watch more in the interview above with Martha MacCallum.