Mark J. Terrill / AP

The strange, sad tale of Donald Trump and Jeb Bush continues.

After first trying to ignore the billionaire bigot, and then getting humiliated by him, Jeb is now making his willingness to stand up to Trump the centerpiece of his campaign. He’s just released an ad entitled “The Only One,” in which he slams Ted Cruz, Marco Rubio, and Chris Christie (a sure sign that Christie’s surge in New Hampshire is real) for not attacking Trump. By contrast, the ad shows Jeb lustily going after the GOP frontrunner, while words like “chaos candidate,” “unhinged,” and “liberal” flash onto the screen.

At first glance, this seems laudable. But there are a couple of problems. For starters, Jeb can’t attack Trump without triangulating. In his ad, Jeb doesn’t merely denounce Trump for endorsing Vladimir Putin’s murder of journalists. He also denounces him for being “liberal.” This summer, when Trump was calling undocumented Mexican immigrants “rapists,” Jeb did something similar. He said Trump’s immigration policies would “violate people’s civil liberties” but also that they’re “not grounded in conservative principles” because they’ll cost too much. It’s like saying George Wallace was a bad presidential candidate because he opposed African American equality and because he supported too much government spending. When told of Trump’s comments about Hillary’s “disgusting” trip to the bathroom during the Democratic presidential debate, Jeb did it again. He said that, “Trump is not going to be president because he says these things, it turns people off.” But he added that, “This will enhance her victimology status. This is what she loves doing.” More triangulation. In Jeb’s view, Trump was wrong to insult to Hillary for, essentially, being a woman, and Hillary was equally wrong for being insulted.

The other problem with Jeb’s attacks on Trump is that when you look closely, they’re less about Trump’s views than about his demeanor. Jeb’s ad calls Trump “unhinged” and a purveyor of “chaos.” Asked about Trump’s Hillary bathroom line, Jeb said Trump lacks “decorum.” He went on to exclaim, “For crying out loud, we’re two days before Christmas. Lighten up, man.”

Trump’s candidacy is based on bigotry and lies. But Jeb never says that. Instead, he criticizes Trump for being too emotional, too unruly, too fervent. It’s less the content of what Trump says that offends Jeb than the manner in which he says it.

This seems to be something of a Bush family trait. They’re sticklers for protocol. Among the ways in which George W. Bush believed Bill Clinton had disgraced the presidency was by entering the Oval Office without a jacket and tie. One of Bush’s aides, Dan Bartlett, recounts being “chewed out for about 15 minutes” by Bush for trying to enter the President’s office on a Saturday wearing “khakis and a buttoned-down shirt.” George W. was also fanatical about punctuality. And since leaving the presidency, he has adhered scrupulously to another rule of good etiquette that the Bushies take deadly seriously: Don’t criticize your successor.

It’s the same with George H.W. Bush. In November, biographer Jon Meacham made news by revealing that the elder Bush had criticized Donald Rumsfeld and Dick Cheney. But Bush’s criticism focused less on Rumsfeld and Cheney’s ideology than on their style. Bush described Rumsfeld as “kick ass and take names, take numbers.” He called Cheney “iron-ass” and accused him of “knuckling under to the real hard-charging” hawks in the White House and Pentagon.

Jeb, like his brother and father, prizes decorum. He wants presidential candidates to behave like gentlemen. In the age of Trump, that’s kind of sweet. But it plays right into Trump’s critique of Jeb as “low energy.” Jeb detests Trump for being unable to regulate his emotions. But it’s precisely Jeb’s insistence on regulating his emotions that has left him unable to channel the rage that grips much of the GOP base.

Jeb isn’t only telling Trump to “chill out.” Implicitly, he’s saying the same thing to his party’s voters. Which helps explain why he’s trailing Trump by roughly 30 points in national polls.

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