The news on Wednesday that Donald Trump has finally – finally! – hired some people to run his campaign signaled that the candidate has made his general-election pivot.

Or rather, his general-election double-down.

Republicans who are worried about a blowout loss in November must have felt heartened at the headlines blaring "Trump Campaign Shake-Up." But like most things Trump-related, that brief flare of hope was quickly snuffed by news of who Trump was putting in charge: Steve Bannon. That Trump has chosen Bannon to run the show tells us two things. First, the campaign is about to get much nastier. And second, conservative media activists have now completed their takeover of the GOP.

Bannon is the head of Breitbart, the pugnacious website so deep within the Trump camp that it attacked its own reporter when she publicized that she had been manhandled by Trump's then-campaign manager, Corey Lewandowski (now at CNN). Breitbart's style is attack-dog journalism that keeps the innuendo thick and the fact-checking light.

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Bannon himself comes from a business and entertainment background, making his money first in banking, then television. He has no political experience, but that hasn't stopped him from taking the reins of a major-party presidential campaign. (Sound like anyone you know?)

Add in Trump's consultations with Roger Ailes, the one-time political consultant turned Fox News chief turned disgraced ex-employee, and right-wing media have completed their ascension within the GOP. It's the end-point of a process started nearly half a century ago – a process I detail in my new book on conservative media – when Richard Nixon began wooing National Review writers as a way of securing conservative support. Nixon was smart enough to keep conservative media in his outer orbit, inside the gates but not much closer.

But as right-wing media became more powerful and more profitable, they gained more of a toe-hold in Republican politics. Struggling for re-election in 1992, George H. W. Bush reached out to radio sensation Rush Limbaugh to help rally the right to his side. To secure his support, Bush invited Limbaugh and his then-television producer Ailes to sleep over at the White House. Two years later, when Newt Gingrich led the Republicans to victory in the midterms, his victory party was emceed by local radio host Sean Hannity.

As these relationships grew more symbiotic, Republican politics began to take on some of the features of conservative media. More oppositional, less open to compromise. More red-meat rhetoric, less outreach to new groups. And perhaps most importantly, more and more of what Julian Sanchez has called "epistemic closure," as Republicans rely on ideas, issues and language developed in the echo chamber of right-wing media.

Donald Trump, who espouses right-wing populism more than straightforward conservatism, occupies the darker corners of this echo chamber. He brings together the conspiracism of InfoWars, the vulgarities of Ann Coulter, the incuriosity of Sean Hannity, the savagery of Breitbart. This is a place where Khizr Khan is not a grieving Gold Star father but a secret architect of either 9/11 or the Islamic State group, where birtherism still thrives, where Hillary Clinton isn't an opponent but an enemy of the state.

With Bannon at the helm and Ailes on speed-dial, the Trump campaign has decided to make its last stand on this poisoned ground. As Robert Costa tweeted earlier today: "Gloves off. Brutal fights with Clinton. Heavy emphasis on nationalism and populism. That's the Bannon strategy." It's also the Breitbart strategy, and now the Trump strategy.

The Trump campaign to-date has been conducted with little regard for truth or decency, and the Bannon strategy means more of the same. That such a strategy won him the Republican nomination should lead to considerable soul-searching, not just from party insiders but from the conservative media complex that made Trump possible.