By Stephen Collinson, CNN/StyleMagazine.Com

While triggering global geopolitical shockwaves, North Korea's nuclear test also represents a flagrant personal challenge to President Donald Trump and his strategy of escalating the showdown with Pyongyang with explosive rhetoric.

With his previous threat to rain "fire and fury" on North Korea and warning that the US military is "locked and loaded" to respond to Kim Jong Un's provocations, Trump set up a test of wills with his unpredictable adversary.

Now, with his nation's most powerful nuclear detonation Sunday and a string of missile launches, including one over Japan, Kim has effectively called the President's bluff, escalating a dangerous foreign policy crisis.

Trump's options to prevent North Korea twinning a nuclear device with an intercontinental ballistic missile that could reach the US are narrowing, and with each North Korean move, the time available to act is running out.

Every time that the Trump administration has hiked pressure and rhetoric against Pyongyang, through sanctions, condemnations and military maneuvers and exercises, Kim has upped the ante in its showdown with Trump.

In this, the Trump administration is not alone -- nothing the previous three US administrations did to halt North Korea's nuclear program worked either -- with the isolated state on an arc to building a deliverable nuclear device.

Personal element

Those who support Trump's bombastic rhetoric say that since sanctions and pressure and diplomacy have in the past failed to slow North Korea's nuclear and missile program, the President's more approach is worth a try.

But Trump has injected a particularly personal note into his confrontation with Kim, putting his own personal authority and credibility on the line in a way that worries some national security experts.

Former CIA and National Security Agency director Michael Hayden told CNN's Dana Bash on "State of the Union" Sunday that he believed that Trump's national security team had framed a coherent policy on North Korea, especially in its effort to impress upon the Chinese the urgent need to use more of its influence to change North Korea's behavior.

But he said that the approach had sometimes been "inartfully executed" and warned that the President should avoid being drawn in to a mano-a-mano showdown with Kim in the wake of the nuclear test.

"I fear two things. The stray electron, the tweet that just goes out a 5 a.m. and unintentionally creates effects that make this go to a place where we don't want it to go," Hayden said. "The other one is this. We just got into a duel with the North Korean chairman, with Kim Jong Un. If we had a choice of weapons, I think it was a bad choice to get into a hyperbole contest with that kind of guy."

"Mr. President, this is not a manhood issue, this is a national security issue. Don't let your pride get ahead of wise policy here," he added.

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