WASHINGTON ― Sen. Mitch McConnell (R-Ky.) once told me that he wanted to be remembered as Kentucky’s second Henry Clay, the 19th-century lion of the Senate known as the “Great Compromiser.”

But McConnell, now the Senate leader, on Thursday ensured that his legacy ― and that of other recent leaders of both parties ― will be as the “Great Dividers,” amplifying partisanship in an era of rising, crippling conflict.

Following in the footsteps of an equally partisan Democrat, Harry Reid, McConnell reduced the Senate to a grayer, more verbose House. Congress as a whole now is less the deliberative engine the Founding Fathers envisioned than a de facto, dysfunctional parliament.

Democrats, now led by Sen. Chuck Schumer (D-N.Y.), are part of this sad story. They demanded a filibuster-level 60-vote supermajority to confirm President Donald Trump’s Supreme Court nominee, Neil Gorsuch. In so doing, they dared McConnell to use a procedural option that Reid had pioneered to reduce the needed vote to a mere majority. Despite his professed reverence for Senate tradition, the Kentuckian was happy to oblige.

The Supreme Court is collateral damage. In the process of ramming through Gorsuch, McConnell ensured that the court will be seen even less as the above-it-all interpreter of the Constitution, and even more as a nakedly political, unelected legislative body filled with permanently partisan justices.

Does any of this matter? If you think the founders knew what they were doing, yes. We are heading down the road to what they feared: government by plebiscite. They were worried that a clever demagogue (can you think of one right now?) would overwhelm minority rights and views ― and even just plain common sense ― in the tide passion of a bare majority.

The founders well knew the House of Commons in London, and they knew the monarchy, and they strove to avoid both in America.

In the U.K.’s House of Commons, political parties sit opposite each other, a sword’s length apart. They heckle and jeer across the distance like rivalrous football fans. But the parliamentary majority has total control, and can force its agenda through as long as its leaders hold their own troops in line.

It’s efficiency at the expense of a loud but powerless minority.

The Founding Fathers looked at this and wanted nothing of it. A new, diverse, continental country, they thought, needed practical engines of cohesion and consensus more than ideological (or in the case of England in the old days, religious) purity.

The founders feared both the monarchy and the mob. To counter the former, they substituted the Constitution for the divine right of kings (with justices as the secular, law-reading high priests). To cool the passions of the latter, they adapted an idealized view of the Roman Republic in the form of the U.S. Senate.

Now, both the Senate and the Supreme Court are in danger of losing what is left of their special character ― the character that made us what we were.