If the 230-year American democratic experiment unravels — no longer an unthinkable possibility — the postmortem should focus on what happened in the Senate this week.

The majority Republicans could have put the brakes on President Trump and forced the rewriting of his travel ban on seven Muslim-majority countries. They chose not to.

The sloppily executed travel ban, produced under the auspices of attorney general nominee Jeff Sessions, has been blocked in part by federal judges, while the acting attorney general, doubting the order’s legality, said she would not defend it. Trump aides reacted with conflicting signals of whether they would honor the court orders and by firing the acting attorney general — Trump’s own version of Richard Nixon’s Saturday Night Massacre, after just 10 days on the job.

Many Republican lawmakers voiced their objections. But given a chance to do something about the offending order, they demurred.

The Senate Judiciary Committee met Tuesday morning to vote on the Sessions nomination — a perfect leverage point to force Trump to revise or withdraw the order. Not one of the Republicans made a peep.

(Alice Li,Whitney Leaming/The Washington Post)

One of those on the panel, Jeff Flake (R-Ariz.), had called the order “unacceptable” as written.

But Flake said nothing of that Tuesday morning in his brief statement calling Sessions “a good man.”

Another on the panel, Lindsey O. Graham (R-S.C.), had said in a joint statement with John McCain (R-Ariz.) that the “order was not properly vetted” and that “we should not turn our backs” on blameless refugees, mostly women and children, who “suffered unspeakable horrors.”

But on Tuesday, Graham “enthusiastically” saluted the man behind the order.

Also on the committee: Ben Sasse (R-Neb.), who called the order “too broad” and cautioned that it could help terrorist recruiters.

Sasse didn’t speak at Tuesday’s meeting.

It’s commendable that many Republicans have spoken out against Trump’s travel ban. But the disconnect between what they say and what they do was particularly pronounced Tuesday morning.

(Adriana Usero,Jorge Ribas/The Washington Post)

As The Post’s Philip Rucker and Robert Costa reported, Sessions has been the “intellectual godfather” of Trump’s policies, including the travel restrictions. Key Trump aides Stephen Miller, Rick Dearborn and Stephen K. Bannon have strong ties to Sessions, and Bannon called Sessions “the clearinghouse for policy.”

Roger Stone, a Trump confidant, described Sessions as Trump’s John Mitchell — the Nixon attorney general who wound up in prison after an earlier constitutional crisis.

It’s not much of an exaggeration to describe the current situation as a constitutional crisis — except in this instance, those in the legislative branch have quickly surrendered the Article I authorities given them in the Constitution.

There’s a strong case that Trump’s unilateral action violates federal law, and the cavalier treatment of court orders is worrisome regardless of the outcome. But Senate Republicans have twice blocked attempts by the Democrats to rescind the order — swallowing their own misgivings along the way.

Back in December 2015, Senate Majority Leader Mitch McConnell (R-Ky.), asked about Trump’s proposed Muslim ban, said, “We’re not going to follow that suggestion.” He called the proposal “completely and totally inconsistent with American values.” Six months later, he was still arguing that “a kind of broad ban is a bad idea.”

Now Trump is doing just such a ban in the affected countries, a Muslim ban in all but name, and McConnell is punting: “It’s going to be decided in the courts as to whether or not this has gone too far.”

Democrats delayed action on three of Trump’s nominees Tuesday to protest the executive’s caprice, but ultimately only the majority GOP can stop Trump. And the Republicans will never have more bargaining power than they have now, with several of Trump’s Cabinet nominees unconfirmed.

Democrats forced a one-day delay in the vote on Sessions with long-winded speeches on the Judiciary Committee. “This is an administration that needed only one week to find itself on the losing side of an argument in federal court,” Patrick J. Leahy (D-Vt.) said. “Never, ever seen anything like that.”

Mazie Hirono (D-Hawaii) tied the Muslim ban to the internment of U.S. citizens and noncitizens of Japanese descent during World War II, and she praised Republicans such as Sasse, Flake, Graham and Orrin G. Hatch (Utah) for their critical statements.

But what about actions?

Hatch had previously encouraged Trump to “move quickly to tailor its policy . . . as narrowly as possible.”

But he didn’t press the point Tuesday, instead calling Sessions’s qualifications “unmatched in American history.”

Chairman Charles E. Grassley (R-Iowa) had cautioned about the need to remain “a welcoming nation.”

But on Tuesday he concentrated on Sessions’s “integrity.”

Mike Lee (R-Utah), also on the panel, had previously raised “questions” about Trump’s order.

But he had no questions Tuesday. Lee praised Sessions’s “deep commitment to the notion” that “laws govern us rather than the will and whim of individual humans.”

That was the notion, anyway — until 10 days ago.

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