"I think that we have to consider that option as the very last option," the Arizona Republican said Sunday in an interview with CNN's Jake Tapper on "State of the Union."
McCain, the Senate Armed Services Committee chairman, pointed to North Korea's proximity to Seoul, the heavily populated capital of South Korea, saying that in a shooting war, "the carnage would be horrendous."
The Arizona Republican, who was held prisoner by the North Vietnamese during the Vietnam War, said the United States must pressure China to help persuade North Korea to abandon its nuclear ambitions and stop testing ballistic missiles.
"Their capabilities of firing artillery on Seoul is absolutely real," McCain said. "And this is, again, why we have to bring every pressure to bear, and the major lever on North Korea today -- and maybe the only lever -- is China."
"But to say you absolutely rule out that option, of course, would be foolish," he said of the prospect of a