One of President Trump’s favorite words is “strong.” His obsession with strength leads him to a love for unilateral announcements, denunciations of staff members by way of showing who is in charge, and Twitter wars designed to prove that he will not back down from any fight.

Oh yes, and he also thinks he looks strong when he defies all the norms of decency and presidential decorum, as he did in a typically self-involved and, well, bonkers speech in Moon Township, Pa., on Saturday night. He also apparently thinks that another way of showing how tough he is is to propose executing drug dealers and to say he got the idea from China’s increasingly dictatorial leader, Xi Jinping.

Yet Trump is also a pleaser who likes to make those in his immediate company happy by convincing them that he is absolutely on their wavelength. You could see this in his flip-flopping on policy toward both guns and immigration. Recall that the positions he took on any given day depended upon who was in the room with him.

Eventually, he will default to preserving his electoral standing. He was never likely to break with either the National Rifle Association or the hard-line nativists who are at the heart of his administration and his political base. Trump has interests. He doesn’t have a philosophy.

But above all, he has needs, and the erratic nature of the Trump presidency can be explained by the interaction of his two compulsions: looking strong and being liked. They sometimes seem to collide, but they are actually of a piece. Both speak of a man for whom the personal is the only kind of political. It is impossible to know what his true policy commitments are because they are secondary. On any given day and at any given moment, his actions are dictated by what, in his eyes, will make him look forceful and bring him accolades.

Bear all this in mind in assessing the two major events of recent days: Trump’s tariffs on steel and aluminum, and his agreement to enter direct talks with North Korean dictator Kim Jong Un.

The tariffs may, in fact, serve him well in the short term. Note that Trump initially reached his decision to impose them when he was feeling “angry” and “increasingly isolated,” as Post reporters Philip Rucker, Ashley Parker and Josh Dawsey wrote on March 3. With the investigation by special counsel Robert S. Mueller III gathering steam and other scandals dominating the airwaves, Trump did what he always does: He sought to change the subject and shake up the news cycle.

But there is more. If Trump and the Republicans have reason to worry that the political energy of his foes could play out in substantially increased Democratic turnout in this November’s elections, there is a second danger almost as serious. His working-class supporters — the key swing group in the states that gave him his electoral college victory — have little to show for his presidency.

While this past Friday’s robust jobs report provided continued good news overall, it found that wage growth was nearly flat. And as Post blogger Greg Sargent observed last week, economic growth remains concentrated in the states that rejected Trump. “Trump Country” is not experiencing the renaissance he predicted, in part because he could not have kept his outsize promises in the first place.

Thus Republican nervousness about Tuesday’s special congressional election in a western Pennsylvania district that backed Trump by nearly 20 points. If Republican Rick Saccone loses to surging Democrat Conor Lamb, or prevails only narrowly, it will be a stark warning that the GOP could face decimation this fall even in the president’s heartland.

While Trump scaled back the reach of the tariffs from his original proposal, they still sent a loud message to his straying base: Remember the old me; I’m still here. That was also the message Trump sent in his rambling, in-your-face speech Saturday on behalf of the struggling Saccone. Should the GOP prevail on Tuesday, count on Trump to tout the tariffs opposed by most of his party (and, of course, his unplugged performance in Moon Township) for pulling the race over the line. His agreement to meet with North Korea’s brutal and erratic leader is an even bigger showstopper. It was variously cast as a great triumph for Trump’s hard line or a foolish and premature concession that enhanced Kim’s standing without gaining anything in return. On Friday the White House tried to condition the meeting on “concrete steps” from North Korea, but then Trump insisted he was going full speed ahead. He was not about to let go of the Trumpian point to it all: He was doing something no other president dared do while casting himself in a starring role.

All presidencies are shaped by the personal proclivities of the occupant of the Oval Office. But we have not had a president who focused so much energy on appearing to be strong and who, like the playwright Arthur Miller’s salesman Willy Loman, so desperately wants to believe he is “liked.” These drives are the biggest threats to Trump himself and, I fear, to our republic.

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