In a matter of 72 hours, while celebrating the "achievements" of his first 100 days in office, he spoke in a manner unbecoming a U.S. president, sent inconsistent — if not dangerous —messages to allies and adversaries alike.

To add insult to injury, he invited Philippine President Rodrigo Duterte, accused of committing genocide against his own people in his war on drugs, to the White House. And he said he would be "honored" to meet with North Korean dictator Kim Jong Un, calling him a "smart cookie."

Of course, at the same time, he was threatening a pre-emptive strike against Pyongyang.

Talk about cognitive dissonance!

He said he didn't understand why the Civil War couldn't be "worked out" and suggested that Andrew Jackson might have been able to stop it. Nevermind that Jackson was dead 16 years before the Civil War began and that he, himself, owned 150 slaves.

(Frederick Douglass, who the president recognized not too long ago as " an example of someone who has done an amazing job and is being recognized more and more," is likely rolling over in his grave somewhere close to Jackson's.)

In an utterly incomprehensible interview with CBS anchor, John Dickerson, the president rambled on about his unfounded allegations that President Obama "wiretapped" the incoming president.

When pressed for details, he then summarily, and on camera, dismissed Dickerson from the White House.

His own chief of staff confirmed that the president has looked into either amending, or abolishing, the First Amendment. The bedrock amendment on which this nation was founded is an apparent insult to presidential prerogatives.

This, as the president recently referred to the entire Constitution as "archaic." That document is the very one and only, upon taking the oath of office, he has sworn, and is required, to uphold.

It is quite clear that this president is unfamiliar with constitutional law and, understandably, may not yet heard about the 25th Amendment.

For his edification, Section IV of the Amendment states:

"Whenever the Vice President and a majority of either the principal officers of the executive departments or of such other body as Congress may by law provide, transmit to the President pro tempore of the Senate and the Speaker of the House of Representatives their written declaration that the President is unable to discharge the powers and duties of his office, the Vice President shall immediately assume the powers and duties of the office as Acting President."

Since taking the oath of office, he has impugned his predecessors and, according to some published estimates, made over 400 unsubstantiated claims in the mere three months he has sat in the Oval.

And, since March of 2015, when then citizen Trump began exploring a run for the White House, I maintained that he did not have the requisite skills, temperament or character to occupy the Oval Office.

His most recent behavior not only confirms those observations, in my opinion, but also goes well beyond the realm of being simply ill-suited for the job.

For the good of the country, our people, our allies, and to a much lesser extent, even our enemies, Congress should give that amendment a fresh look and, if agreed, make use of it.

103 days already seems too long.

Commentary by Ron Insana, a CNBC and MSNBC contributor and the author of four books on Wall Street. Follow him on Twitter @rinsana.

For more insight from CNBC contributors, follow @CNBCopinion on Twitter.

