President Trump warned North Korea on Thursday that “things will happen to them like they never thought possible” should the isolated country attack the United States or its allies.

Trump told reporters here that his Tuesday statement threatening “fire and fury” may not have been “tough enough,” even as he sought to reassure an anxious world that he has the situation under control.

“Frankly, the people who were questioning that statement — was it too tough? Maybe it wasn’t tough enough,” Trump said. “They’ve been doing this to our country for a long time, for many years, and it’s about time that somebody stuck up for the people of this country and for the people of other countries. So, if anything, maybe that statement wasn’t tough enough.”

[6 questions about North Korea’s quest for nuclear weapons]

As the war of words continued for a third day, Trump made no reference to an undercurrent of concern among some within his administration about his rhetoric, or to the widespread nervousness and disapproval expressed by U.S. allies. The exchanges, including a North Korean threat to Guam, have rattled a world wondering what will be next.

(Elyse Samuels/The Washington Post)

Just this past weekend, the administration was congratulating itself for orchestrating a unanimous U.N. Security Council vote to sharply increase sanctions against Pyongyang, describing steady diplomatic and economic pressure as the keystone of its strategy.

Instead, Trump said Thursday that the administration is now examining its entire military posture in Asia and that “we are preparing for many different alternative events.”

He said that he had already decided to increase the “antimissile” budget “by many billions of dollars, because of North Korea and other reasons.”

Last spring, the United States installed a Terminal High Altitude Area Defense, or THAAD, anti-ballistic-missile system in South Korea.

Trump’s latest comments on the North Korea crisis came in remarks to reporters before and after a national security briefing at his private golf club here, where he is on a working vacation. Seated around a table with the president were Vice President Pence, CIA Director Mike Pompeo, White House national security adviser H.R. McMaster and homeland security adviser Tom Bossert. Chief of Staff John F. Kelly and several other aides were also in the room.

The threat to Guam, made after his initial “fire and fury” remarks, was “a whole new ballgame,” Trump said. North Korean leader Kim Jong Un was “not getting away with it,” he said, adding, “He’s not going to be saying those things, and he’s certainly not going to be doing those things.”

“He does something in Guam, it will be an event the likes of which nobody’s seen before, what will happen in North Korea,” he said. “It’s not a dare. It’s a statement.” Kim, Trump said, was “not going to go around threatening Guam and he’s not going to threaten the United States and he’s not going to threaten Japan and he’s not going to threaten South Korea.”

View Graphic North Korea has launched 18 missile tests in 2017, and 13 were successful.

Trump said that the Security Council vote was gratifying and that he remained open to negotiating with Pyongyang. But, he said, talks over the years under previous administrations had done little to halt the country’s nuclear program. “What they’ve been doing, what they’ve been getting away with, is a tragedy, and it can’t be allowed,” he said.

In Twitter comments Wednesday that were clearly directed at North Korea, Trump also warned that the U.S. nuclear arsenal was “now far stronger and more powerful than ever before.” It would remain the world’s strongest, he said Thursday, until the world decides to get rid of nuclear weapons altogether.

“Nuclear to me, number one, I would like to de-nuke the world,” he said. “I know that President Obama said global warming is the biggest threat. I totally disagree.” But until denuclearization happens, Trump said, “nobody, including North Korea, is going to be threatening us with anything.”

Thursday’s security briefing and the president’s statements came after two days of mixed messages from the administration.

On Tuesday, Trump delivered an unusually bellicose threat to North Korea, warning that further provocations from Pyongyang “will be met with fire and fury like the world has never seen.” His language was improvised and had not been reviewed by his national security advisers or political aides.

The North Koreans effectively laughed off his remarks, calling them a “load of nonsense” and outlining their plans to fire missiles into the waters off Guam, a strategically located Pacific island and home to U.S. military bases.

Senior administration officials then sought to calm anxious world leaders as well as Americans. But statements from Secretary of State Rex Tillerson, Defense Secretary Jim Mattis and senior White House officials, including adviser Sebastian Gorka, varied widely in tone and to some extent in substance, ranging from sober and reassuring (Tillerson) to forceful yet measured (Mattis) to bellicose in the style of the president (Gorka).

Mattis, in a statement released Wednesday by the Pentagon, said that “while our State Department is making every effort to resolve this global threat through diplomatic means,” allied militaries “now possess the most precise, rehearsed and robust defensive and offensive capabilities on Earth.”

Later Wednesday, in comments not released by the Pentagon until Thursday, Mattis told a pool of reporters traveling with him to the West Coast, where he planned to visit technology companies, that “of course there’s a military option.” But “we want to use diplomacy. That’s where we’ve been, that’s where we are right now, and that’s where we hope to remain.”

Asked about Trump’s “fire and fury” comments, Mattis said: “The rhetoric is up to the president. This is my rhetoric.”

After Trump’s remarks Thursday, Mattis, in Silicon Valley, paused before commenting. “My portfolio, my mission, my responsibility is to have military options if you need it,” he said. “However, right now you can see . . . the American effort is diplomatically led, has diplomatic traction and is gaining diplomatic results. And I want to stay right there right now. The tragedy of war is well enough known. It does not need another characterization beyond the fact that it would be catastrophic.”

Gorka was asked Thursday by BBC News about the apparent divergence between Trump and his senior Cabinet advisers. “You should listen to the president,” he said, adding that it was “simply nonsensical” that Tillerson would deal with “military matters.”

“We are not giving in to nuclear blackmail any longer,” Gorka said. Asked about critics such as Sen. John McCain (R-Ariz.), who called Trump’s rhetoric provocative, he replied that “there is only one person in this great country that controls our nuclear arsenal, and it’s not John McCain.”

At the State Department on Thursday, spokeswoman Heather Nauert responded sharply to Gorka’s comments on Tillerson: “I can say that I speak for Secretary Tillerson and this building. . . . Our secretary has been very clear, as has been Secretary Mattis, that our diplomatic and military means are both strong and capable.”

Asked whether Tillerson’s push for diplomacy was being heeded elsewhere in the administration, Nauert said: “He’s a Cabinet secretary. He’s fourth in line to the presidency. He carries a big stick.”

Tillerson, who returned Wednesday from a lengthy Asian trip on which he sought to build support for full implementation of the new sanctions, made no public appearance.

Meanwhile, the Associated Press reported that Kuwait’s government said it would continue to grant visas to North Korean laborers, whose wages allegedly aid the Pyongyang government, despite a sanctions provision prohibiting their employment.

The AP quoted a Kuwaiti government statement saying “there are no plans to expel” some 6,000 North Korean laborers working there.

Nauert said the statement had been “brought to our attention” and that the administration was in “close contact” with the Kuwaitis. “We understand that the government of Kuwait will be issuing a [new] statement imminently,” she said.

About an hour later, the Kuwait News Agency posted a statement from the country’s foreign ministry saying that “pursuant to the UN Security Council resolution on economic sanctions on North Korea, the State of Kuwait no longer issues entry visas for North Korean workers or licenses for commercial activities and halted direct flights from the country.”

DeYoung reported from Washington.

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