Ex-national security adviser John Bolton responds to Trump's tweets about his memoir

John Bolton fired back at Donald Trump on Thursday after the president unleashed a firestorm of critical tweets about his former national security adviser and his new book, "The Room Where it Happened."

"I think it's unbecoming of the Office of President," Bolton said Thursday. "I think it degrades the political civil discourse in our country and [I'm] just not going to respond to him."

Trump called Bolton a "sick puppy" and a "wacko" on Twitter and said his new memoir -- set to be released next week -- is...