“I hope to have God on my side,” Abraham Lincoln is reported to have said as the Civil War began and the alignment of border states was in doubt, “but I must have Kentucky.” The national GOP hopes to have a reelection of President Trump while retaining its Senate majority. But the party must have Kentucky — in the form of Mitch McConnell, the Senate majority leader from that state. His able stewardship of the chamber that James Madison described to Thomas Jefferson as the great “anchor” of the scheme of government that issued from the Philadelphia Constitutional Convention of 1787 has been essential not only to Republicans, but also to the nation itself.

Two years ago I wrote of McConnell’s approach to judicial appointments who will respect America’s founding document, saying that it “is not an overstatement to say that Senate Majority Leader Mitch McConnell has saved the Constitution as we know it.” Now, at the end of a tumultuous four years and as the 2020 election careens to a wild conclusion that is impossible to predict because the country is so deeply divided, McConnell remains the indispensable man.

McConnell has, in effect, served as Trump’s prime minister through the first term, and would do the same should Trump surprise as he did in 2016 and summon unexpected majorities in critical states and the Senate remain in Republican control.

Some Democrats have radical plans that must be blocked by the Senate. They want to “pack” the Supreme Court by adding new justices; destroy the legislative filibuster; make D.C. a state (unconstitutionally, in my view); and seek stunningly high taxes and spending long after the pandemic has passed. McConnell as majority leader would stop these plans cold — to the benefit of all Americans.

In the Senate, there must be moderate Democrats who secretly hope for McConnell’s continued tenure as majority leader. Blaming him and railing against his legislative dark arts are preferable to being regularly confronted by votes on a radical agenda. These moderates no doubt long for the day when their party is more firmly moored to a traditionally liberal agenda. Institutionalists understand that the legislative filibuster, with 60 votes needed to pass most legislation, developed as an extra-constitutional additional “check” in the “checks and balances” scheme of 1787. They don’t want to be bum-rushed into wrecking the chamber. McConnell, with at least 50 Republican colleagues, would save the Constitution a second time if former vice president Joe Biden wins the election.

McConnell’s first great task — reviving the federal courts as a bulwark of individual liberty and protector of the separation of powers — will be complete with the confirmation of Judge Amy Coney Barrett to the Supreme Court. The Republicans’ painstaking, four-decade clawback of power from the administrative state will then reach its high-water mark. Free speech, free exercise of religion, property rights, the rights of the accused and of others facing down the state will flourish under a court headed by Chief Justice John G. Roberts Jr. and buttressed by the arrival of this superb legal scholar. Despite the pandemic, one senator told me, McConnell will see to Barrett’s confirmation, even if he has to dress his members in hazmat suits for the vote.

The Barrett confirmation will complete a great quartet of McConnell achievements. First came his guiding the Republican Senate majority to hold open the Supreme Court vacancy after Justice Antonin Scalia’s death, when the Senate and executive branch were held by different parties and an election loomed. Second, McConnell cannily adapted the procedural ruthlessness of Harry M. Reid (Nev.), his Democratic predecessor as majority leader, who changed Senate’s rules to confirm by a simple majority all judicial nominees save Supreme Court justices; McConnell extended the Reid rule to apply to the Supreme Court with the 2017 confirmation of Justice Neil M. Gorsuch. Third, McConnell stood resolute and secured the confirmation of Justice Brett M. Kavanaugh in 2018, despite a media frenzy and slanderous attacks on the nominee.

Now, with Barrett, McConnell will have his fourth master stroke, almost certainly repairing a great breach in the Constitution that began half a century ago when the left commandeered the court for the purposes of legislating from the bench instead of applying the law.

Much consequential legislation has been passed during McConnell’s tenure in recent years, including the prison-reforming First Step Act, massive changes in the tax code, repeal of Obamacare’s individual mandate and pandemic relief that has saved countless businesses and jobs.

But it will be the three new Supreme Court justices and 53 federal appeals court judges (so far), and the safeguarding of the Founders’ principles, that mark McConnell’s contribution to the nation. In the 19th century, Henry Clay, the Kentucky senator, was called “the great compromiser.” McConnell deserves the sobriquet of “the great constitutionalist.”

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