When people, notably women, say "men are boys with more expensive toys", they mean cars, boats or golf clubs. Not a university, a foundation or a beauty pageant; and certainly, not drones, cruise missiles and Inter-Continental Ballistic Missiles.

But now we've got a man who demonstrated once and again that he's got the "temperament, language skills and emotional age" of a teenager holding the most powerful office in the land and with direct access to the nuclear codes.

What is America to do about it? What are the rest of us to do, especially those at the receiving end of American power (bearing in mind that in one year only, in 2016, the US has dropped more than 26,000 bombs on mainly Muslims nations)?

First, one needs to understand the gravity of the situation. Foremost, just why and how Donald is dangerously adolescent.

Think about it

The few references to Trump's immaturity that I came across seem to be no more than expressions of amusement or, at worst, signs of frustration and exasperation. They don't reflect a true understanding of the dangers and implications of Trump's troubled mind now that he's been elected president.

It's been observed that the 6ft 3in 70-year old man acts like a 17-year old high-school bully. It's a behaviour that every boy and girl who went to school understands.

More disturbingly, Donald suffers from each and every symptom of teen-aging.

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Starting with the most typical behaviour: staying up late, watching videos, and using different forms of communication gadgets to send awful, ridiculous and awfully ridiculous messages. I mean seriously, who does that at 70? Who but an adolescent snaps at trashy rumours and insinuations at 4am?

According to the specialists, part of being a teenager is being thin-skinned; even the smallest things set them off. In that way, any random satire, criticism or inquiry seem to set off Trump like a powder keg.

And with Trump it's always drama, the very opposite of no-drama Obama. He threatened to contest the elections if he didn't win, and now that he's won, he reckons any investigation into a Russian hacking is a "witch-hunt".

This goes into one of those more teenage contradictions characterising Donald's behaviour as he oscillates like a pendulum between attention-seeking and utter insecurity; between "me, me, me" and "they all hate me".

All of these might not be so terrible if he only "mans up" upon taking the reins of power. But Donald also suffers from what the specialists call "Oppositional Defiant Disorder symptoms".

Troubled old man

Trump shows all four symptoms of a troubled teenager: irritability; argumentativeness, defiance, and vindictiveness.

When President Obama insisted Trump doesn't have the temperament to be president, he was alluding to the fact that the silliest things infuriate him and he doesn't think before shooting back with little or no consideration for the consequences.

Really, how could anyone trust someone with such a character; someone who loses his temper in a flash? Let alone trust him with the nuclear codes?

What if another adolescent leader with small hands and big missiles started brandishing them to test, irritate or even blackmail the US? How will Trump respond?

Trump argues and argues about the stupidest, most inconsequential things such as his looks. A double, triple or quadruple chin? And he never admits mistakes. Rather, he prefers to blame his faults on others.

And like a brat, he insists on being first. And when he isn't, it's always someone else's fault.

But even when, by hook or crook, he does come first, Trump can't stop himself annoying others with his defensiveness. His new year's tweet was a stark illustration of that as he wished love to everyone "including my many enemies and those who have fought me and lost so badly they just don't know what to do". Really!

And he's above all vindictive. He never lets go. As when Fox News host Megyn Kelly questioned him during the earlier presidential debates about his abusive treatment of women, he haunted her for months. Calling her names and turning terribly abusive in public, so much so that the network had to take precautions against possible threats on her life by Trump supporters.

Will he change?

Can Trump change now that he's become president? Strangely enough, a good number of people in Washington reckon the presidency could change him. They at least hope so.

But is that realistic, at 70? Or, is it wishful thinking? Besides, hasn't he gotten worse with each and every win since the primaries began?

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He seems to feel vindicated, even empowered, by his own excesses, like a rowdy teenager who considers any sign of approval a licence to get rowdier and brasher.

This behaviour should worry everyone in and outside America.

What if it happened?

What if another adolescent leader with small hands and big missiles started brandishing them to test, irritate or even blackmail the US? How will Trump respond? What's to become of the Koreas and security in the South China Sea?

Well, guess what? This is no longer hypothetical.

Last week, Kim Jong-Un boasted of his country edging closer to test-launching an ICBM. Trump responded with a tweet: "It won't happen!", but without providing any explanation.

But what will stop Kim Jong-Un from testing such a missile that could reach the US shores, if successful? What if he did it soon after the inauguration by way of testing the new president's new red line? I mean, it's not as if he hasn't been testing missiles!

Trump will have only two real options: diplomacy or military action.

For the diplomacy or sanctions to work, he needs Beijing. But Trump has been inciting against China like there's no tomorrow. And Beijing is more than happy to see him boxed in or even humiliated.

As for military action, it's sure to have devastating consequences on North Korea's neighbours, South Korea and Japan, which, by the way, Trump encouraged rather irresponsibly to get nukes during the presidential campaign.

What else could be done to bring a swift resolution to such a stand-off? What could prove to the whole world that Trump is not a chump; that he means business?

Oh, no! Not that.

The US must assure the world that President Trump does not stay up late watching videos and toying with the " football" come January 20. The nuclear football.

Marwan Bishara is the senior political analyst at Al Jazeera. Follow him on Facebook.

The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.