As one of my friends put it, “How does a man go from being one of our nation’s bravest soldiers to a career politician so desperate to remain in office at the age of 80 that he will sell out the very Constitution he swore to defend?” Jonathan Chait, who for years has covered the slow institutional decay of the Senate, shakes his head over McCain as well —then looks ahead:

People predict that the U.S. population will continue to get younger, better educated, and less white. I hope our political experiment lasts long enough to see that day.

We have what might be described as an asymmetric politics. One party disagrees with the other party’s policy domestic policy positions, but recognizes the legitimacy of an opposition party and accepts that the other party is patriotic and loyal to the country. The other party rejects the legitimacy and loyalty of the other party. The efforts to de-legitimize former President Clinton, President Obama, and likely future President Hillary Clinton are part of this effort. The refusal of the GOP Congress to allow Obama any legislative accomplishments was another part of it. I expect that a GOP House will adopt the same obstructionist tactics starting in 2017.

I understand that their thinking is that they don’t want the bias of the Court to shift from conservative to liberal. But the Court has shifted back and forth over the years, and we have managed to survive those changes. Apparently, today’s Republican Party feels that the country somehow won’t survive a Democratic administration or a liberal Supreme Court.

I don’t know if your readers have seen this yet, but it seems that McCain has announced that his fellow GOP Senators will not confirm any Supreme Court nomination by Clinton . Trump is an ignorant, narcissistic, nasty piece of work. But McCain used to be a guy who remembered and honored (at least sometimes) the old bipartisan traditions of the Senate. His statement is just outrageous and inexcusable. What he’s basically saying is that only Republican presidents get to appoint Supreme Court Justices.

First there was McCain’s caving to Bush’s signing statement on his own torture bill, then his selection of an extremely unqualified and unvetted running mate, then he backed Trump until nearly the bitter end—even after Trump insulted his POW experience and his fellow vets with PTSD. And now, a shameless betrayal of constitutional principle that would have gotten far more attention this week if Trump hadn’t one-upped McCain with all his incendiary “rigged” rhetoric. Reader Don explains:

If Clinton wins and Democrats pull enough Senate seats, Republicans will oppose her nominee, and then, eventually, Democrats will change the rules to abolish filibusters of Supreme Court nominees. (Republicans will decry this foul measure and justify any subsequent actions of their own as justified revenge.) If Clinton wins and Republicans hold on to 51 seats, they will simply refuse to let any nominee through. The fact that it is McCain, a personal friend of Clinton and as strong an institutionalist as can be found in the Senate, who is proposing to extend the blockade indefinitely shows just how deep the commitment runs through the party.

Here is Fallows on “the mystery of John McCain” … way back in 2010, when McCain was obstinately opposing the repeal of DADT during Senate hearings—clearly on the wrong side of history, in a petty way that excluded gays and lesbians from openly serving their country:

I have been trying to think of a comparable senior public figure who, in the later stages of his or her career, narrowed rather than broadened his view of the world and his appeals to history's judgment. I'm sure there are plenty (on two minutes' reflection, I'll start with Henry Ford and Charles Lindbergh), but the examples that immediately come to mind go the other way. George C. Wallace, once a firebrand of segregation, eventually became a kind of racial-healing figure near the end of his troubled life. There was something similar in the very long and winding path of Strom Thurmond (or Robert Byrd). Or Teddy Kennedy, who sharpened the ideological edge of his rhetoric as the years went on, but who increasingly valued his ability to work with rather than against his Republican counterparts in the Senate. Barry Goldwater went through the same evolution from the opposite starting point. Lyndon Johnson and Robert McNamara, different kinds of peaceniks by the end. We know that for humanity in general, the passing years can often make people closed-minded and embunkered in their views. But for people in public life, it seems to me, surprisingly often the later years bring an awareness of the chanciness and uncertainty of life, the folly of bitterness, the long-term advantage of a big-tent rather than a purist approach. John McCain seems intentionally to be shrinking his audience, his base, and his standing in history. It's unnecessary, and it is sad.

For more on McCain’s steady decline, peruse these Dish posts. Also, one of the best eye-opening pieces of the 2008 election was Tim Dickinson’s, “John McCain: Make-Believe Maverick: A closer look at the life and career of the candidate reveals a disturbing record of recklessness and dishonesty.”

If you have any views on McCain’s career or latest ploy, especially if you can defend him, send us a note and we’ll post: hello@theatlantic.com. Update from a regular Notes contributor, William: