At some level, at a basic gut level, this Trump thing was always about The Wall: The Wall as an imposing physical entity, The Wall as a symbol. The Wall as the emotional centerpiece of every rally.

Donald Trump knows it. He knows it better than anyone. He knows that The Wall represents his covenant, his mutual pledge of faith to the people with the red MAGA hats on their heads and the adoring looks on their faces. The promise to build the Wall embodies his promise to serve as their protector and shield against unwanted outside influences.

Against immigrants. Against imported goods, imported ideas. Against demographic change and economic change. Trump would stop all that, and The Wall would be tangible proof of that commitment.

“People want the border wall,” as Trump told the Associated Press. “My base definitely wants the border wall, my base really wants it — you’ve been to many of the rallies. OK, the thing they want more than anything is The Wall.”

His base does want it. In poll after poll, large majorities of Americans reject the idea of a wall. They understand the futility and expense of it, and they want no part of it. But a consistent minority — 37 percent in a new ABC News/Washington Post poll — say they support it. Twenty-five percent say they support it strongly. That is the Trump base, the people to whom Trump feels a real connection, affection and obligation. They give him what he needs, which is adoration. And he owes them The Wall in return.

“I could stand in the middle of 5th Avenue and shoot somebody and I wouldn’t lose voters,” Trump has bragged, and he’s probably right. But abandon The Wall? That might be different.

The Wall would protect; it would divide and separate, us from them. It would do more than just prevent the flow of drugs and immigrants across the border, because in fact it would do none of those things. The Wall would make a statement.

That over there? That’s their side; this is our side.

And the fact that Mexico would pay for The Wall?

That has always been about power, about the joy of imposing our will upon and humiliating a weaker neighbor. The pledge to make Mexico pay for The Wall, which Trump still insists will happen, was about far more than finding the pesos for the construction costs. At the emotional level where this all found resonance, making them pay for the wall was about making “them” pay for a whole slew of perceived acts of disrespect against America, not just by Mexico but by the entire world.

The Mexicans understood all that — humiliation is not a subtle thing. They got it. And when, as a matter of national pride, Mexican leaders categorically refused to pay for The Wall, you no doubt remember Trump’s smug response.

“The Wall just got 10 feet taller, believe me. It just got 10 feet taller.”

And you probably also remember the raucous, gleeful response.

But in the end, here’s another way in which The Wall epitomizes all, because there will be no wall. Unable to generate support from Democrats in Congress and from a number of Republicans as well, Trump says he will delay his push to fund The Wall until September.

But September will come and September will go and there will still be no wall, for the same reason there’s no Nigerian prince wanting to put $10 million into your bank account.