Appearing Sunday on CNN's "State of the Union," McCain - the top Republican on the Senate Armed Services Committee -- was asked how the most recent ratcheting-up of tension compares to past instances.
"I think it's probably more serious because of their increased capability," he said. "But you're right, this has been going on for decades: a cycle of confrontation, negotiation, aid, and the false hope that somehow the North Koreans would give up their efforts to acquire nuclear weapons and the means to deliver them. Without that, North Korea is totally irrelevant."
McCain called on China, North Korea's only ally in the region, to do more to address the situation.
"China is the only country that can affect North Korean behavior. They can shut down in a short period of time their economy," McCain said. "So what China needs to do is start squeezing [the North Korean] economy. Without China, their economy would collapse in a relatively short period of time."