Michael Hayden, the former head of the NSA and CIA, thinks some of presidential candidate Donald Trump's campaign promises are so unlawful that the U.S. Armed Forces could not follow them as orders.

These include Trump's claim that people deserve to be waterboarded even if it doesn't work and that he would target the families of terrorists. The internationally recognized Geneva Conventions bars such action.

"If he were to order that once in government, the American armed forces would refuse to act," Hayden said Friday during an appearance on "Real Time with Bill Maher." "You are required not to follow an unlawful order that would be in violation of all the international laws of armed conflict."

Hayden added that he would be "incredibly concerned" if Trump followed through with his campaign promises as president.