Here's what you need to know about the Breitbart News chairman who just became Donald Trump's new campaign CEO. (Jenny Starrs/The Washington Post)
Opinion writer

If you thought the old Donald Trump campaign was wild and crazy, just wait for the new Trump campaign now that Breitbart’s Steve Bannon has taken over as chief executive.

The new leadership — with Bannon and pollster Kellyanne Conway displacing Paul Manafort of the Ukrainian Connection at the top of the heap — is likely to steer Trump even more in the direction of the European far right. It also tells you something that Bannon sees Sarah Palin, about whom he made a laudatory documentary, as a model for anti-establishment politics.

Bannon is close to Nigel Farage, the former head of the right-wing U.K. Independence Party, who offered “massive thanks” to Breitbart News for supporting the party’s successful campaign on behalf of Britain’s departure from the European Union. “Your UKIP team is just incredible,” Bannon told Farage during an interview after the June Brexit vote.

Judging from Bannon’s history, Trump’s campaign will become even harsher in its attacks on Hillary Clinton and work hard to insinuate anti-Clinton stories into the mainstream media. Bloomberg Businessweek’s Joshua Green quoted Bannon proudly declaring in mid-2015: “We’ve got the 15 best investigative reporters at the 15 best newspapers in the country all chasing after Hillary Clinton.”

And count on Trump to ramp up his appeals to Bernie Sanders’s supporters and the left. Pushing his anti-Clinton film “Clinton Cash” in May, Bannon said he wanted progressives to “understand how the Clintons, who proclaim to support all your values, essentially have sold you out for money.” In his conversation with Farage, Bannon expressed great interest in the role played by left-of-center voters in Brexit’s victory.

Republican presidential nominee Donald Trump, who's spent months touting his ability to "win," has recently started to discuss the possibility of losing the election – a surprising move for a candidate. (Peter Stevenson/The Washington Post)

A Trump news release Wednesday bragged about the headline on Green’s important Bloomberg Businessweek article describing Bannon as “the most dangerous political operative in America.” The new CEO poses dangers not only to Clinton, but also to Republicans such as House Speaker Paul D. Ryan (Wis.) who have been tiptoeing around their party’s nominee by simultaneously criticizing him and endorsing him. Bannon has no use for Ryan. A December piece Bannon co-wrote began: “Paul Ryan’s first major legislative achievement is a total and complete sell-out of the American people masquerading as an appropriations bill.”

Bannon could thus speed the defection of longtime GOP officeholders, while Senate and House campaigns are likely to become even more distant from Trump. In his past endeavors, Bannon targeted not only Clinton but also Jeb Bush. Trump’s relations with the Bush wing of the party could hardly be worse, but Bannon is likely to make them impossible.

There is much good news but one piece of bad news for Clinton in the Trump shake-up. The bad news is that she is likely to have to play more defense, especially if Bannon builds on his success in enticing reporters at non-conservative media outlets to work on stories damaging to her.

The good news is that Trump seems determined to fight through the campaign on his own terms. This reduces the chances that he will drop out of the presidential race, which, in turn, means that Clinton is more likely to avoid what would be the biggest blow to her chances: a Trump withdrawal and the naming of a new GOP candidate.

Trump’s campaign is also likely to look more extreme, which cannot help the flailing candidate in the suburban, highly educated precincts in states such as Pennsylvania, Virginia, Colorado and North Carolina where he is hemorrhaging more upscale Republican votes. Bannon’s fascination with Palin, who turned off many such voters to John McCain after he chose her as his running mate in 2008, could aggravate, rather than ease, this problem.

And if the theme of this latest bit of Trump court intrigue is a return to the “Let Trump be Trump” philosophy, Clinton’s operatives will only cheer. Trump being Trump is precisely what led him to this crisis point.

Bannon’s rise dramatizes the catastrophe GOP establishmentarians brought upon themselves by imagining that they could use the far right for their own purposes while somehow keeping it tame. Bannon’s European interests suggest he is far more impressed by right-wing third parties than by traditional Republicanism. He believed the anti-establishment rhetoric that Republican politicians deployed but never really meant when they were attacking President Obama. Now, the GOP faces the possibility of a real split.

It fell to Palin in her January endorsement of Trump to tell the party establishment off: “We are mad, and we’ve been had. They need to get used to it.” They are unlikely to get used to Bannon.

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