If you were looking for a two-word slogan to describe Donald Trump's life, that would be a fitting one. In everything -- from the size of his buildings to the size of his genitals to the size of his nuclear arsenal, Trump is totally and completely obsessed with being the biggest and the best.

"North Korean Leader Kim Jong Un just stated that the 'Nuclear Button is on his desk at all times.' Will someone from his depleted and food starved regime please inform him that I too have a Nuclear Button, but it is a much bigger & more powerful one than his, and my Button works!"

"Much bigger & more powerful." "My Button works."

If you don't see what Trump is going for there, then we need to have a side conversation about the birds and the bees. This is a measuring contest provoked by the President of the United States against an unstable dictator pursuing a nuclear capacity.

It's absolutely stunning given the stakes: Nuclear war/annihilation. At the same time, it's an entirely predictable tactic from Trump given what he we know about him.

Let's remember that in the 2016 Republican primary process, Trump got into a pissing contest -- almost literally -- with Florida Sen. Marco Rubio about genital size.

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At a rally in early March, Rubio said this of Trump: "He's like 6-foot-2, which is why I don't understand why his hands are the size of someone who is 5-foot-2. And you know what they say about men with small hands? You can't trust them."

Days later -- at a GOP primary debate -- Trump made sure to address the Rubio allegation.

"Look at those hands, are they small hands?" Trump said while displaying his mitts. "And he referred to my hands -- 'if they're small, something else must be small.' I guarantee you there's no problem. I guarantee."

I guarantee you there's no problem.

Trump's obsession with size is evident in ways large and small -- ahem -- throughout his life.

There's dozens more examples just like these, but you get the point. In Trump's mind, the first, second and third most important measures of success are size. Everything he is involved with must be the biggest, the tallest, the most well-attended, the most expensive, the best.

A bit of armchair psychology would suggest that relentless focus on size is born of insecurity.

Remember that Trump has always viewed himself as an outsider, scorned by the cool kids. His father was a successful developer, but not in Manhattan, where the big boys played. Trump went into Manhattan and built right in the heart of it, but the major players in the city's power structure didn't like him or let him into their clubs. When he came to Washington in 2011 considering a potential political career, the establishment laughed at him during the White House Correspondents Dinner

In Trump's mind, he is always on the outside looking in. And he is motivated by a desire to stick it to the elites who have shunned him his entire life.

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The way to do that -- in Trump's mind -- is to always one-up whoever is challenging him. If you build a 95-story skyscraper, he'll find a way to build a 96- story one. If you got 50,000 retweets, he'll want to get 100,000. And, if you have a nuclear button ready to push on your desk, well you can sure as hell bet Trump has a bigger and better nuclear button on his desk.

Trump's size obsession was mildly amusing when he was a private citizen. The man who always had to have the biggest toy.

But, as President, his compulsive need to not only have the biggest and the best everything but to shove it in the face of world leaders that he has the biggest and the best everything takes on an entirely different feeling -- one of uneasiness about whether the President of the United States grasps what his size contest obsession means in a world of nuclear weapons.