Analysis by Stephen Collinson, CNN

(CNN) -- Donald Trump potentially has millions of lives in his hands as the threat of a devastating war with North Korea swiftly escalates.

Yet the President of the United States is raising new questions about his temperament, his judgment and his understanding of the resonance of his global voice and the gravity of his role with a wild sequence of insults, inflammatory tweets and bizarre comments.

On Wednesday Trump caused outrage and sparked fears of violent reprisals against Americans and US interests overseas by retweeting graphic anti-Muslim videos by an extreme far right British hate group. Earlier this week he used a racial slur in front of Native American war heroes. He's attacked global press freedom, after cozying up to autocrats on his recent Asia tour.

And now there are reports that the President has revived conspiracy theories about former President Barack Obama's birthplace and is suggesting an "Access Hollywood" video on which he was heard boasting sexually assaulting women, and for which he apologized last year, had been doctored.

In normal times, it would be a concern that the President is conducting himself in a manner so at odds with the decorum and propriety associated for over two centuries with the office he holds.

But the sudden escalation of the North Korean crisis, following the Stalinist state's launch of its most potent ever missile on Tuesday, takes the world across a dangerous threshold.

If diplomacy is unable to defuse the North Korea crisis, or slow its march to the moment when Kim Jong Un can credibly claim to be able to target all of the United States with a nuclear payload, Trump will face one of the most intricate dilemmas of any modern President. Will he live with the threat posed by a mercurial, wildly unpredictable adversary? Or, will he launch what could turn out to be a hugely bloody and destructive war to remove Kim's nuclear threat?

There will be a premium on Trump's judgment, his capacity to absorb the most serious detail and to make choices that could put many, many lives at risk, and draw the United States into escalating situations in Northeast Asia.

Alternative truths

For years, Trump, living his life in the glare of the New York tabloids took refuge in convenient alternative truths, constructed his own version of reality and actively promoted conspiracy theories. He maintained that model of behavior as a candidate and a President. But the fact such conduct is coinciding with what could evolve into a major global crisis will force his staff, fellow world leaders, the media and the public to grapple with the implications.

That's the context in which Trump's recent behavior is coloring and is the reason why this moment could turn about to be more significant than the unorthodox and unconventional months of his presidency up to now.

It's also why its fair to ask questions about his state of mind when, for instance, retweeting explosive videos of doubtful authenticity featured by the far right nationalist group Britain First, as he did on Tuesday.

"I have no idea what would motivate him to do that," former Director of National Intelligence James Clapper said on CNN's "New Day" on Tuesday. "To me, it's bizarre and disturbing, particularly when I think of him doing that in the context of North Korea, where moderation, and temperance and thought I think is critical."