McCain, R-Ariz. the chairman of the Senate Armed Services Committee, added that China will be "key" in how the world addresses the situation.
"They can stop this if they want to because of their control over the North Korean economy," McCain said on "Meet the Press."
"There are artillery on the border between North and South Korea that can reach Seoul and we can't take them all out before — I mean, this is a very serious. This may be the first test of this presidency. But China can shut them down. Whether they are currency manipulators or not, we should expect them to act to prevent what could be a cataclysmic event."
Early Sunday morning local time, North Korea attempted to launch a missile, but U.S military officials told NBC News that it failed "almost immediately."
In a statement Saturday, U.S. Defense Secretary James Mattis said, "the president and his military team are aware of North Korea's most recent unsuccessful missile launch. The president has no further comment."