U.S. Defense Secretary James Mattis, echoing the warnings of President Donald Trump, said North Korea can expect a “massive military response” if it threatens the United States, the U.S. territory of Guam or America's allies.

White House officials said the president emphasized the range of retaliatory measures available to the U.S., including nuclear weapons, in a conversation earlier with Japanese Prime Minister Shinzo Abe: “President Trump reaffirmed the commitment of the United States to defending our homeland, territories, and allies using the full range of diplomatic, conventional, and nuclear capabilities at our disposal.”

Mattis, Trump and the president’s top advisers met at the White House Sunday about North Korea’s announced hydrogen bomb test. The Pentagon chief came out to talk with reporters briefly afterwards to say the U.S. is not looking for the “total annihilation” of North Korea, but “we have many options to do so.”

North Korea’s repeated provocative ballistic missile tests and now a sixth nuclear test seens as perhaps the first time Pyongyang has successfully detonated a thermonuclear device have presented Trump with this most critical geopolitical crisis of his young administration.

"Secretary Mattis expressed the only viable option in his statement, which is a firm and clear deterrent policy toward North Korea," said Hoover Institution Fellow Michael Auslin.

However, Auslin told VOA, the goal of North Korea's denuclearization, which Mattis also repeated Sunday, is unrealizable.

“Continuing to insist on denuclearization means further rounds of negotiations, and the past quarter-century has shown that negotiations do not work,” he says. “The Trump administration has the opportunity to chart a new, more realistic course for U.S. policy, but not if it adopts the failed policies and goals of previous administrations.”

Other analysts and officials reacting to the extraordinarily stark remark from the Pentagon chief are hoping for diplomatic discussions instead of more tough military talk.

Mattis’ “imprecision was counterproductive. Will there be a massive military response against any ‘threat’? This word choice was a blunder along the lines of the promise of ‘fire and fury’ against any North Korean threats,” said Frank Aum, a visiting scholar at the U.S.-Korea Institute.

Aum, the former senior adviser for North Korea at the Defense Department, told VOA: “It's telling that the defense secretary was the one who was addressing the press. We need to get away from a military-centric approach to the North Korea problem set and reinvigorate diplomacy.”

The president, leaving a church service near the White House earlier Sunday, said only, “We’ll see” when a reporter asked if he was planning to order an attack on North Korea.

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