J. Scott Applewhite / AP

The last two weeks have been an emotional roller coaster for many Americans, but it’s unlikely many of them can match John McCain’s experience.

About two weeks ago, the Arizona senator was diagnosed with a brain tumor after an operation to remove a blood clot in his head. Last Wednesday, that diagnosis became public. By Tuesday, he’d flown back in to Washington for a critical vote to open debate on an Obamacare repeal bill. First, he cast the decisive vote to proceed to the debate, handing Republican leadership a big win, and then he delivered an impassioned speech, taking Republican leaders (and the president) to task for their process on the bill.

Finally, early Friday morning—despite entreaties from Senate Majority Leader Mitch McConnell, Vice President Pence, and President Trump himself—McCain cast another decisive vote, this time to reject the latest repeal attempt, dubbed “skinny repeal.”

As his decision became clear on the Senate floor, McCain drifted away from dejected Republicans and toward Democrats, who grinned and hugged him. But the episode seems to help clarify McCain’s status as he reaches the twilight of a long Senate career. John McCain is not, despite some of the most fevered denunciations, a man without principle. Under intense pressure Thursday night and into Friday morning, he refused to budge. But his principles are unusual—he values process, decorum, and Senate traditions to a degree that many observers find strange—and anyone who expects him to be a hero for their own ideological cause is likely to be disappointed.

Start with McCain’s dramatic return to the Senate. Trump, who famously derided McCain during the presidential campaign (and had issued a strangely terse statement after his diagnosis) suddenly lauded McCain as a hero:

Some liberals held out a weird hope that McCain would dramatically return to the floor, play the maverick, and defeat the vote to open debate; or they hoped he’d vote against it just to spite Trump. He didn’t. After much anticipation, and a thunderous ovation, he cast his vote to open debate, thus guaranteeing a 50-50 tie for Pence to break. Trump was delighted:

The speech McCain delivered after he cast the vote was a peculiar one, and in retrospect one to which Trump (and perhaps McConnell) should have paid closer attention. McCain lamented the departure from the slow, deliberative process of the Senate. He pled for bipartisanship. He warned that victory per se was not more important than the nature of that victory.

“It is our responsibility to preserve that, even when it requires us to do something less satisfying than winning, even when we must give a little to get a little,” he said. “Even when our efforts manage just three yards and a cloud of dust, while critics on both sides denounce us for timidity, for our failure to ‘triumph.’”

He also indicated that the proposals that McConnell was pushing—no one had yet seen any actual legislative text—were not to his liking.

“We try to do this by coming up with a proposal behind closed doors in consultation with the administration, then springing it on skeptical members, trying to convince them that it's better than nothing,” he said. “That it's better than nothing? Asking us to swallow our doubts and force it past a unified opposition—I don't think that's going to work in the end, and probably shouldn't.”

McCain’s speech engendered two major reactions. Some people took it as a rousing message and a profile in old-school Washington principles. Others, including me, found the exercise a bit strange. Here was McCain, pleading for a return to regular order, but then justifying his vote on procedure. He seemed to be trying to have it both ways: Having declared that the world was upside down, he was stubbornly insisting on voting as though it were right-side up. In retrospect, that view was not entirely wrong, but it was too harsh. McCain’s logic still makes limited sense, but he proved that he would remain true to it with his vote Friday morning.

In explaining his vote, McCain correctly described the bill as barely deserving the name. His close friend Lindsey Graham seemed to share similar objections to the bill, but agreed to vote for it after Speaker Paul Ryan agreed to a conference committee with the House. Graham seemed to believe that, even though the House plans had been more conservative than the Senate ones, and even though no GOP plan thus proffered would lower premiums and expand care, a Hail Mary in conference would somehow solve the problem. McCain wasn’t buying that deviation from standard process.

“While the amendment would have repealed some of Obamacare’s most burdensome regulations, it offered no replacement to actually reform our health-care system and deliver affordable, quality health care to our citizens,” he said in a statement. “The Speaker's statement that the House would be ‘willing’ to go to conference does not ease my concern that this shell of a bill could be taken up and passed at any time.”

He added: “We must now return to the correct way of legislating and send the bill back to committee, hold hearings, receive input from both sides of aisle, heed the recommendations of nation’s governors, and produce a bill that finally delivers affordable health care for the American people. We must do the hard work our citizens expect of us and deserve.”

It was a tough lesson for Trump, who has gotten more than a few of them since entering the White House: Don’t expect McCain to be your hero. He might bail you out from time to time, but not out of personal fidelity to the president. Actually, as James Hohmann notes, McCain has a long a memory and good reason to feel genuine resentment toward Trump; while perhaps that played into his decision, the justification McCain offered fit with his own, unusual obsession with process.

Democrats would do well to pay attention to that, too. They may find themselves grateful to McCain Friday, but they should not take that as evidence that he’s their hero, either. McCain loves procedure, but he doesn’t love Obamacare. “From the beginning, I have believed that Obamacare should be repealed and replaced with a solution that increases competition, lowers costs, and improves care for the American people,” he said in his statement. He said he still wants to see repeal and a replacement; he just wants to do it through a more open, normal procedure.

Interpretations of McCain these days seem to veer between lionizing him as a man of conscience, usually defined by how closely the senator hews to the observer’s own political priorities, or as a callow fraud, trading on the “maverick” reputation when in reality he is more likely to talk a good game but not to play it. (This is one reason his speech on Tuesday seemed to me a likely case of actions separated from words.) That binary is a little reductive, and it sidesteps the centrality of process to McCain’s choices. The traditions of the Senate can seem not only inscrutable but pointless to outsiders. Obeisance to them can sometimes make one look like a maverick, as it did Friday, or like a sheep, as it did on Tuesday. Certainly, it can seem silly to prioritize them over policy outcomes or party goals. But it is an ethos, and it’s one to which John McCain stayed true this week.

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