This story, originally published in June, has been updated.

By now, it’s a given: Nearly every time he addresses supporters or gets a chance to list his accomplishments, President Trump takes a dig at Sen. John McCain (R-Ariz.).

Even, it seems, when the event is in honor of McCain. On Monday, Trump smashed through yet another political norm when he signed a defense-spending bill named after McCain and didn’t mention the senator. Not content to let the very obvious snub sit at that, Trump took it a step further hours later. At a fundraiser in New York, Trump did mention McCain’s name, but it was in the context of dissing the senator he just ostensibly honored with a bill signing earlier in the day.

Trump has displayed a remarkable lack of sensitivity to McCain’s very serious health problems and his stature in the Republican Party. McCain was diagnosed with brain cancer a year ago and hasn’t been in the Senate since December to cast a vote. He’s also one of the most senior members of the Senate, and one of the most respected. It’s not every day a major spending bill is named after a U.S. senator, but McCain, a Vietnam War hero and chair of the Senate Armed Services Committee, has spent decades pursuing many of the big items in this key piece of legislation for the military.

Yet Trump still frequently frames McCain as a spoiler to the Republican Party’s legislative success this past year. He blames McCain for his party’s failure to repeal Obamacare — or at least sees him as a reliable scapegoat. In one week in June, Trump brought up McCain’s surprise “no” vote last summer that ended Republicans' efforts to gut Obamacare three times in the past four days.

“We were very surprised by one gentleman,” Trump said in June while speaking to reporters at the White House.

And at a rally in South Carolina on a day earlier: "[H]e campaigned on repealing and replace, we had all the votes, and perhaps he was grandstanding, who knows what he was doing? But you know what? He said, ‘No, no.’ Everybody said, ‘What the hell happened?’ He’s been campaigning for eight years — repeal and replace. And he didn’t do that.”

And at a rally in Nevada a few days earlier: “Nobody talked to him. Nobody needed to, and then he walked in: Thumbs down.”

And at a rally in Minnesota a week earlier: “We had a gentleman way into the morning hours go thumbs down. He went thumbs down.”

The dissing goes all the way back to a rally Trump held in McCain’s home state of Arizona in August shortly after the vote and McCain’s announcement he had brain cancer.

If anything, since the diagnosis, Trump and his allies have ramped up their criticism of McCain. The most outrageous instance of that was in May, when a White House aide went so far as to make light of the senator's health behind closed doors. The White House refused to publicly apologize when those comments leaked.

McCain has mostly kept his recent criticism of the president to policy, though in his own statement about the defense spending bill, he notably didn’t mention Trump either. His daughter Meghan McCain, who has become a kind of spokeswoman for the family, recently called Trump’s repeated, onstage mockeries of her father “gross.”

Trump does have reason be wary of McCain. If there is a battle for the soul of the Republican Party, McCain is still the face of its anti-Trump wing, even from home in Arizona.

McCain has criticized Trump’s foreign policy as “half-baked spurious nationalism,” urged opponents of Trumpism to “fight” it and tried to torpedo Trump’s pick to lead the CIA by urging his colleagues to vote against her.

Trump’s mockery of McCain doesn’t make much political sense when you dig into it. McCain has been home in Arizona all year to treat his cancer, and it’s not clear when he will return to Washington. The form of brain cancer he is battling is a particularly aggressive one.

Plus there are lots of reasons an Obamacare repeal failed; McCain’s opposition was just one of them. He wasn’t the only Senate Republican to vote against it, but Trump may have zeroed in on how his “no” was the most surprising and dramatic. McCain’s thumbs down on the floor of the Senate toward the end of a late-night vote elicited gasps among those present.

At the time, McCain said he didn't like the backdoor process by which the bill came to form. In his new book, “The Restless Wave,” McCain wrote that he thought the bill didn't do much beyond undoing current law: “I’m not sure we’ll ever agree on a replacement, and so perhaps all we can do is try to fix parts of Obamacare.”

Trump immediately started blaming Republican leaders in Congress for failing to repeal a law they campaigned for seven years to undo. For whatever reason, Trump has since settled on solely blaming McCain.

Inadvertently or not, McCain has played an outsized role in Trump’s political rise. Barely a month into his presidential bid, Trump touched what many in politics thought was a third rail when he described McCain as “not a war hero.” The two men never really stopped crashing into each other.

Trump has somehow turned mocking one of the Republican Party’s living legends into a political tagline that usually appeases any Trump-friendly crowd he’s talking to. Using the party’s ailing figurehead as a foil is just one more political norm Trump has smashed as president.