A Surprising Show of Confidence Trump’s speech was clear, plain, even warm at times. Could we be seeing a capacity to grow?

The president’s speech has been broadly, justly praised. Here, a look at particular aspects of the joint session address, and why it had power.

First, the baseline accomplishment. Much has been said in the press about the sin of normalizing Donald Trump, but with this speech—by being there at the podium in the august House chamber, and operating capably and within established traditions and boundaries—he normalized himself. He doesn’t need the favor anymore.

People watching would have had a better opinion of him by the end of the speech than when they began. And those who abhor Mr. Trump got a glimpse, for once, of what his supporters saw and see in him.

Donald J. TrumpOn CNN Van Jones said—acutely, bravely, yet I think incorrectly—that Mr. Trump became president during the speech. I think instead Mr. Trump was finally understood to be president during the speech—by everyone, even those who oppose him and call him illegitimate. That, for such a unique character, was achievement enough.

Second, it was a good speech. It was clear and plain and at points had a surprising sweetness. He stuck to his usual policy sternness and yet added rhetorical warmth. There was a lot of braggadocio—“A new national pride is sweeping across our nation”—but there was also something more important. To get to it I mention something that is misunderstood about Ronald Reagan.

The cliché is that Reagan’s power was his optimism—he walked into the room with the sun’s rays dancing on his shoulders, and that made everything better. That’s not true. Reagan wasn’t precisely an optimist. He didn’t assume history unspooled each day in the direction of improvement; he didn’t necessarily think the best thing would happen. What was true was that Reagan was confident—in his own powers and those of the American people. He was confident we could make the right decisions and turn things around. People saw that confidence, and it allowed them to feel optimistic.

Confidence, in a president, is important. Mr. Trump’s speech was confident. He rose politically by painting an America in bleak decline, but here he insisted our problems are not irreversible. “Everything that is broken in our country can be fixed. Every problem can be solved. . . . The challenges we face as a nation are great. But our people are even greater.”

It showed something like faith, and was powerful. This is one of the things people need, the sense that if we hold together and back the right plans we can get the arrows on the graph going upward again.

There was a heartening plainness. Mr. Trump told a story of meeting with officials and workers from Harley-Davidson. “They proudly displayed five of their magnificent motorcycles, made in the USA, on the front lawn of the White House.” He asked them how they were doing. “They told me—without even complaining, because they have been so mistreated for so long that they’ve become used to it—that it’s very hard to do business with other countries, because they tax our goods at such a high rate.” One country, they said, taxed their motorcycles at 100%. “They weren’t even asking for a change. But I am. . . . I am not going to let America and its great companies and workers be taken advantage of any longer.”

Mr. Trump recast his second, forthcoming executive order on immigration as motivated by prudence and a desire to protect: “It is not compassionate but reckless to allow uncontrolled entry from places where proper vetting cannot occur.” He spoke of “our friends and allies in the Muslim world.” If he’d spoken this way early on, the first order would not have caused the uproar it did.

On ObamaCare’s repeal and replacement, the key phrase was “stable transition.” That appears to mean: If you now have coverage and previously lacked it, or if you’ve been forced onto a new plan and fear losing it, we’re going to spend the money it takes to protect you.

This will not be unpopular. The American people have watched for a generation as their federal government half-ruined the American health-care system. They won’t find it unjust that the government gives the victims of its efforts a break.

It was good that the president began the speech damning bigotry of all kinds: “We are a country that stands united in condemning hate and evil in all of its very ugly forms.” This is not a hard thing to do rhetorically, yet is always important and necessary, because it reminds everyone in this fractious, bubbling, stressed and many-cultured country that we owe each other respect and regard, not only tolerance but affection. We won’t continue as a people unless we get this right.

The president has taken to doing this lately. Why did he resist so long? Maybe in part because a man who believes himself unbiased will find it grating that others insist he personally, publicly, repeatedly oppose the ugly isms. Maybe he feels he has nothing to prove and suspects bowing to the demand is tantamount to conceding that he does. But Mr. Trump did have things to prove, because of the views of a highly vocal sliver of his supporters. In any case, presidents should say the right things.

There is something the leaders of populist, nationalist movements here and in Europe do not understand. They are not powerful, because they are perceived, on some level, by some people, to be racist or narrow or anti-Semitic. They fail to win power—they have low electoral ceilings, or fail to win half the votes—because of this perception. It doesn’t help them, it kills them. Because the majority of people don’t like the smell of sulfur.

Nationalists should actively and publicly reject and rebuke the forces of darkness. “We need them to win”? No, they’re the reason you lose. They’re not numerous, they’re only loud. Draw a line between them and you, raise your ceiling, get yourself a chance at winning. Which, if you are serious about your programs, vision and philosophy, is the point.

Mr. Trump took a lot of steam out of the Democrats. By the time he movingly lauded the beautiful young widow of a Navy SEAL, the faces of the Democrats on the floor had turned glum and grim. They were sinking in their seats. Politicians know when a politician has scored.

Republicans, on the other hand, were buoyed. As they came to understand the speech was not a disaster but a triumph, they got more enthusiastic and happy-looking. As desperate as they are not to do anything, because to decide is to divide, they are also desperate to do something. Maybe they can with Chief Crazy Horse. All the polls will show a bump for the president. They’ll see it as a bump for the party.

It marks, if not a new chapter, a turning of the page. It suggests Mr. Trump may have a capacity to grow into the office, which is so surprising to me as a thought that I hardly want to commit it to paper. But here it is, in the paper.