CBS News senior national security contributor Michael Morell said Sunday that North Korean leader Kim Jong Un demonstrates "greater and greater capability" with every new missile and nuclear test he conducts.

Morell, a former acting and deputy director of the CIA, also outlined President Trump's options for dealing with North Korea.

Morell said "we don't know for sure exactly" where Kim Jong Un stands when it comes to his ability to put a U.S. city at risk of nuclear attack, but that the test North claimed Sunday marks the "strongest, most significant nuclear test to date."

North Korean state-run media announced the country's latest test Sunday, claiming that it tested a thermonuclear weapon -- commonly called an H-bomb.

Morell said that Mr. Trump's first option is diplomacy -- to "try to convince this person to step back from the brink."

But Morell contends, "That's failed for the last 25 years," adding that there is "absolutely no reason to believe it's going to work now."

Morell said that while "we need to try" a diplomatic approach, he believes diplomacy will fail, which would leave the U.S. with two options.

One is a military option, "which would be probably not be successful in fully degrading his capabilities and could create probably most likely a second Korean war," he said.

"The other option is acceptance of this capability, containment, deterrence just the way we contained and deterred the Soviet Union," he added.

Later on Sunday, U.S. Defense Secretary James Mattis said that "any threat to the United States or its territories, including Guam or our allies, will be met with a massive military response -- a response both effective and overwhelming."

Mattis said that all members of the U.N. Security Council "unanimously agreed on the threat North Korea poses" and remain committed to the denuclearization of the Korean Peninsula. While he said America does not seek the "total annihilation" of the North, he added, "We have many options to do so."

Mr. Trump tweeted Sunday that he would be meeting with Cabinet members and military leaders at the White House to discuss handling the regime's newest threats, writing that "the United States is considering, in addition to other options, stopping all trade with any country doing business with North Korea." Asked if he would attack North Korea, Mr. Trump said, "We'll see."

When it comes to North Korea's capabilities, Morell said there are four elements: