The Republican Party went down to the crossroad and fell down on its knees.

“Have mercy,” the party cried, “and save the poor GOP, if you please.”

And the devil made a pact with the Republicans — the Supreme Court for your soul.

This has always been the understanding.

From the moment Donald Trump became a serious contender for the presidency, mainstream conservatives — on Capitol Hill, in churches and on Wall Street — have been willing to excuse every reprehensible thing about the man for the sake of achieving a long-elusive right-wing agenda. Trump, for all his odiousness, might get them there, they coldly calculated, especially if he kept a campaign promise to appoint only staunch conservatives to the Supreme Court.

EDITORIAL

Trump first came through on his promise last year, putting the circumspect conservative Neil Gorsuch on the court. Now on Monday, he came through again, nominating Appellate Court Judge Brett Kavanaugh, 53, who runs every bit as much or more to the right.

Kavanaugh was among the most zealous true-believers working for independent counsel Kenneth Starr in the furious investigation that led to the impeachment of President Bill Clinton. He also has authored more than 800 appellate court decisions, creating a long record of legal reasoning and positions that is sure to be scoured by Democrats looking to derail his nomination.

If Kavanaugh’s nomination is approved by the Republican-controlled Senate, as expected, a relatively youthful conservative majority could dominate the Supreme Court for a generation.

Presidents come and go. Senators and representatives, too. Executive orders may be issued and rescinded. Laws pass and abolished. But it is entirely possible the court will be handing down retrograde but lasting decisions — on every issue from abortion to health care to religious freedom to voting rights to gay rights to environmental protections to corporate taxation — long after today’s toddlers have grown up and had kids of their own.

The Supreme Court already is fairly steadily conservative, with the retiring Justice Anthony Kennedy’s swing vote usually flapping to the right, and the results have been grim.

Just this spring, the court ruled in favor of a Trump administration travel ban aimed at Muslim visitors, ruled that public employees need not pay fees to the unions that represent them, ruled that anti-abortion pregnancy centers need not inform clients that abortion is an option elsewhere, and declined to question the constitutionality of gerrymandered congressional maps that limit the voting power of minorities.

In each case, the court voted along party lines, 5 to 4, with the conservatives thumping the liberals. Now, with Kavanaugh likely taking Kennedy’s seat, the court’s five conservative justices stand to become the only justices who matter.

We’re not sure how this latest string of conservative rulings has made America “great again.” Not unless the president and his defenders have in mind America of, say, circa 1954, when gay people, women and minorities knew their second-class place.

But we do believe our nation has paid a heavy price for the GOP’s cynical deal at the crossroad.

Trump lies every day, but Republicans don’t call him on it.

Trump turns us against each other, calling Muslims “terrorists,” calling the media “bad people,” and calling undocumented immigrants “murderers.” But the GOP doesn’t so much as cough.

Trump consorts with a porn actress and pays her to keep quiet, but all those “family values” moralizers in clerical collars look away and let it go.

Trump constantly attacks the institutions of our democracy. He claims voter fraud where there is none. He calls the FBI and the Justice Department dishonest for the sin of doing their jobs. He stirs hate and fear, doing his best to drag everybody down to his level.

But who cares about honesty, decency, character and civility when you can take control of the Supreme Court?

Or so says Senate Majority Leader Mitch McConnell, with his silence.

In nominating Kavanaugh, Trump again has picked a tried-and-true conservative for the Supreme Court, even if the judge’s exact views on the hot-button issue of Roe v. Wade, the landmark abortion decision, remain a little murky.

Trump gave mainstream Republicans and conservative preachers what they have always demanded in return for their political support — or for at least their nose-holding silence.

But at what price to the nation?

“I got the crossroad blues this mornin’,” Robert Johnson cried in “Cross Road Blues,” his classic song. “I’m sinkin’ down.”

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