Trump started the conversation about nuclear arms during his call-in on the show with a more restrained approach, calling nuclear weapons "the single greatest problem the world has."
"I don't want to rule out anything. I will be the last to use nuclear weapons," he said, according to Politico. "It's a horror to use nuclear weapons. The power of weaponry today is the single greatest problem that our world has. It's not global warming, like our President said. It's the power of weapons, in particular nuclear."
While Trump said he would be "the last" to use nuclear weapons against ISIL, he also said he would not rule it out.
"I will be the last," he said. "But I will never, ever rule it out."