Every Trump critic had “Oh, hell” moments during the primary season.

They were when Donald Trump demonstrated a keen, gut-level political instinct that even an exceptionally talented conventional politician would be hard-pressed to match.

An example: During a Republican debate in Florida in February, Trump was asked about former Mexican President Vicente Fox’s comment that his country wouldn’t pay for Trump’s “[expletive deleted] wall.”

“The wall just got 10 feet taller,” Trump shot back. The rejoinder was funny and memorable. A Republican senator told me that his cellphone instantly lit up with constituents thrilled at what Trump had said. In slapping down el presidente, Trump advertised his toughness and nationalistic bona fides in a way a $10 million ad buy never could.

Oh. Hell.

Then there was the time he turned Ted Cruz’s “New York values” attack into a riff about 9/11, leaving the college debate champion no option but to applaud Trump’s answer. Or when he made the disruption of a Chicago rally by protesters into an advertisement for his stalwartness against thuggery. Or his temporary ban on Muslims entering the U.S.

You could have locked 100 political consultants in a room and told them not to leave until they had a perfect response to the San Bernardino terror attack, and they never would have come up with it. When Trump proposed the ban, the world collapsed around his head. No one agreed with Trump — except Republican voters. According to exit polls, it was his strongest issue.

The ban is completely unreasonable and, if you were going to try to implement it, impractical. Trump’s insight was that it didn’t matter. Its emotional punch, and the way it differentiated him from the other candidates, was the important thing.

Trump’s achievement is difficult to fathom. With no pollsters, no speechwriters, no fundraising staff, little campaign organization, few TV advertisements, no debate prep and a paper-thin knowledge of public affairs, he has won a major-party presidential nomination. This is a 100-year event.

Trump did it by pounding a simple message over and over again in big rallies and media appearances. His shibboleths are burned into the consciousness of his supporters in a way we haven’t seen since the Barack Obama of “hope and change.” The Trump supporter with whom Cruz argued a few days before the Indiana primary wasn’t highly informed, but he sure knew to shout “Lyin’ Ted!”

The standard rules for political candidates are not to offend and not to court unnecessary controversy. Trump, a creature of the tabloids, has an ingrained instinct to do the opposite. It made him stand out from an initial field of 17, and almost every act of outrageousness reinforced his image as the “truth-telling” outsider.

Trump also was fortunate. For the longest time, there wasn’t any organized effort against him. He won three out of the first four contests while his rivals squabbled among themselves. The establishment initially bet on Jeb Bush, and then, tapped out financially and psychologically, did nothing to rally around Cruz, whom many insiders hate more than Trump.

It seemed that Cruz’s Wisconsin victory was a watershed. In retrospect, it was the beginning of the end. Once it became clear that the only alternative to a clean Trump nomination was a contested convention — with the agony of the primary prolonged two more months and perhaps punctuated by riots in Cleveland — Republican voters seemed to want to shut down the process as soon as possible.

Now it’s on to the next test. At the same time he has lit up 40 percent of the Republican Party, Trump has alienated large swaths of the general public and key voting groups, who are (understandably) not as charmed by his bombast and free-swinging insults. It would be foolish to discount his chances. But it may be that he’s just good enough at this to get into the general, where he will take down a lot of good conservatives with him. Oh, hell.

Rich Lowry can be reached via e-mail: comments.lowry@nationalreview.com.