The Republican Party is screwed.

The news that Chris Christie is endorsing Donald Trump is being absorbed by the Republican establishment as a kind of death knell, and indeed it may be. It suggests that, among some politicians at least, the idea of what the Republican establishment is — and, indeed, what the Republican Party is — is changing.

Trump was the insurgent, the pollutant, the parasite the host would eventually reject. Now he's becoming the power. And that changes everything.

This Chris Christie endorsement of Trump is real signal to GOP establishment that they had better begin thinking about Trump as the future — Newt Gingrich (@newtgingrich) February 26, 2016

The Republican Party is facing a severe collective-action problem. It's not clear Republicans can stop Trump at this point, but if they have any chance, it will take a tremendous mobilization — a coordinated, all-points assault like nothing a political party has managed in the modern era.

At the same time, though, the overwhelming incentive for any individual Republican power player is to defect to Trump's side while the defection will still mean something. Endorsing Trump at a moment when Trump still needs endorsements might net you a job, a kickback, a call of appreciation, something. Endorsing Trump once he's already the nominee is meaningless. Then you're just a pathetic follower. A weakling. A loser.

I am glad you are here with me, Samwise: Here, at the end of all things. — Ross Douthat (@DouthatNYT) February 26, 2016

Christie isn't an outsider. He's a member of the Republican establishment in good standing. He gave the keynote speech at the 2012 Republican National Convention. He was chair of the Republican Governor's Association. He was vetted as Mitt Romney's vice president. He is tied into the party's think tanks, its funders, its advocacy organizations, its interest groups. His endorsement of Trump isn't a sign that he's changed; it's a sign that he thinks what being a member of the Republican establishment means is changing. It used to mean endorsing Mitt Romney. Now it means endorsing Donald Trump.

The Republican establishment is not a secret society in Washington — it's the people who have power in the Republican Party. If Donald Trump wins the Republican nomination, the Republican establishment will quickly become people Donald Trump likes and entrusts with power. So now all the insiders who've fought Trump face a question: Do they hate Trump more than they love being on the inside?

Christie's endorsement follows Trump's first congressional endorsements, which were announced this week. Opportunistic politicians in the Republican Party realize that the establishment may be changing, and right now is a moment when they can secure themselves a space high in the hierarchy of the next Republican establishment. That's a dangerous choice for individual Republicans to be facing at a moment when the party needs to unify against Trump. These endorsements will not be Trump's last.

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