But as someone once wrote in “The Art of the Deal,” “from a bottom-line perspective, bad publicity is sometimes better than no publicity at all.” Mr. Trump won the presidency in part by cornering the market on publicity — much of it bad, but all of it feverish.

The battle to succeed him in the White House will be, in part, a battle to succeed him as the protagonist of our national serial drama, which makes the primary, in part, an audition. It’s easy to imagine Mr. O’Rourke’s border standoff as one in a series of proxy battles to prove the candidates’ media-worthiness.

I know: It is demeaning and depressing to describe the American electoral process as a TV show. Nonetheless it is also true, as proven by the White House’s current occupant. (And not only by him: It was not for nothing that Republicans anxiously tried to dismiss Barack Obama in 2008 as a “celebrity.”)

And while getting media attention is not the same as making policy, it’s not irrelevant to that, either. Alexandria Ocasio-Cortez has gotten almost-unheard-of political influence for a first-term representative in part by being a media star — which is to say, by personifying a narrative, in TV and social media, of a counter-movement further left, more inclusive and younger than Mr. Trump’s own.

Taking on the president in the media doesn’t have to mean imitating him, down to the insults and the Twitter fights. But it does mean being able to seize attention with an alternative story, and sense what the camera is hungry for. To take down the No. 1 show in the country, you need to be an effective counterprogrammer.