US officials confirmed on Wednesday that Donald Trump improvised his threat of war with North Korea.

On Tuesday, Trump followed a scheduled statement on the rise in opioid addiction with an ad hoc declaration of “fire and fury” against Pyongyang over its nuclear and missile tests.

Undeterred by reaction from concern to criticism, Trump followed up on Wednesday with tweets boasting — falsely — about his role in building up the US nuclear arsenal.

Aides say that they knew Trump planned to deliver a tough message on Tuesday, but they did not expect him to use the language which he often uses in private.

On vacation at his golf club in New Jersey, Trump apparently made his statement without consulting Defense Secretary James Mattis, National Security Advisor H.R. McMaster, or Chief of Staff John Kelly — all retired Marine Generals. The outcome defied the line put out by the White House that Kelly — appointed just over a week ago and with Trump in New Jersey — would bring control after the chaos of Executive Branch in-fighting and Trump’s social media outbursts.

Aides expected that Trump would be asked about North Korea after he issued the opioid statement, flanked by Health Secretary Tom Perry. But Trump did not offer a preview in a conference call of what he planned to say. He only mentioning that he wanted to send a signal to North Korean leader Kim Jung-un that he was not backing down, following further revelations of North Korea’s capability for an intercontinental ballistic missile that could carry a miniaturized nuclear warhead.

Aides did not press him because of his resistance over being told what to say.

Trump did not wait to take questions before making his point, instead immediately moving from opioids to his threat. He did so without any notes or briefing paper: “North Korea best not make any more threats to the United States. They will be met with fire and fury like the world has never seen.”

“People close to Trump” say that he believes he has a better understanding of Kim Jong-un than his advisors do, concluding that Kim must be shown that the US cannot be pressed by North Korea’s actions and rhetoric.

According to the sources, while Trump’s statement might cause friction with Kelly, he is more in line with former generals Mattis and McMaster on the issue than he is with his chief strategist Steve Bannon.

Mattis and McMaster favor a tough response to Pyongyang, but Bannon and his allies think that the primary threat is China and Trump should not give prominence to Kim Jong-un.

But one Bannon ally, the hard-right White House advisor Sebastian Gorka, fully backed Trump yesterday in an interview with Fox TV:

He’s saying don’t test America and don’t test Donald J. Trump. We are not just the superpower. We were a superpower, we are now a hyperpower. Nobody in the world, especially not North Korea, comes close to challenging our military capabilities.

North Korea Undeterred

While some advisors loudly defended Trump — Bannon’s hard-right assistant Stephen Miller praised the President as the “greatest orator” in the world — others scrambled to limit any damage.

Secretary of State Rex Tillerson, emphasizing diplomacy, said:

I think Americans should sleep well at night, have no concerns about this particular rhetoric of the last few days. Nothing I have seen and nothing I know of would indicate that the situation has dramatically changed in the last 24 hours.

But Defense Secretary Mattis continued to wave a big stick, appearing to counter Tillerson:

While our State Department is making every effort to resolve this global threat through diplomatic means, it must be noted that the combined allied militaries now possess the most precise, rehearsed and robust defensive and offensive capabilities on Earth….[North Korea] will continue to be grossly overmatched by ours and would lose any arms race or conflict it initiates.

And Pyongyang showed no sign of wavering. The North Korean military said Trump’s warning is a “load of nonsense” and challenged him with the declaration that only “absolute force” will work on someone so “bereft of reason”. Promising that any US strike will be “mercilessly rebelled”, the military said it could “turn the U.S. mainland into the theater of a nuclear war”.

The military specifically threatened Guam, the Pacific island with a strategic US airbase, with the declaration of a plan by mid-August to fire four midrange missiles into nearby waters to create a “historic enveloping fire”.