Donald J. Trump cleared a big hurdle — for him anyway — while he spoke to the nation Tuesday night.

He managed to sound like someone who holds the position he occupies; the president of the United States sounded presidential.

And I give him praise for that. The tone of his voice was measured; he sounded calm; he sounded like a man who well might be starting to grasp the enormous challenges he faces in running a government — and learning that it ain’t a thing like running a business.

However, let’s get past the style and look for a brief moment at the substance of what he said.

He ticked off virtually all the campaign hot-button themes he hit on while running for the presidency. What he has yet to tell us is how in the world he intends to do all the things he has promised to do.

Repeal the Affordable Care Act? Build a “great, great wall across our southern border”? Make our international allies pay for the protection we offer them? Negotiate better trade deals? Do better by our veterans? Find a way to pay for the huge increase in defense spending? Which domestic programs will he cut?

There wasn’t a scintilla of detail in any of it.

I expect it will come. I hope it is soon. I’m on pins and needles waiting to hear how he intends — precisely, specifically — to “make America great again.”

The bar for this president was set pretty low. Sounding presidential shouldn’t be all that difficult for someone who had just won a national election. Until his speech Tuesday night, though, Donald Trump had failed to clear even that low bar. Not even during his inaugural did he sound like a man who had just grasped the reins of power of the greatest nation on the planet. He damn sure doesn’t sound presidential when he fires off early-morning tweets about TV ratings, or late-night comics’ criticism of him.

He managed to sound like a president while standing in front of that joint congressional session.

I want to reiterate this final point: I want Donald Trump to succeed. As it was stated in the film “Apollo 13,” failure is not an option. The consequences of a presidential failure have this way of splashing over all the rest of us.

A friend of mine asked me this morning: What should Trump do to bring the Democrats on board?

Here’s how I responded: He ought to invite the entire congressional leadership team to the White House, sit them all down around a big table and ask this two-part question: What can I do to meet you halfway on these big themes … and what will you do to ensure that we can find common ground?

If the one-time business mogul can grasp the notion that governance requires a partnership between those with different ideological stripes, then I believe success is achievable.

He started Tuesday night at least by sounding like the head of state.