Is the senator now anti-Trump? Well …

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On Friday night, Kentucky Sen. Mitch McConnell strode onto the Senate floor and, without a moment’s hesitation, voted against the Republican president’s nominee for secretary of defense. The vote marked the hard launch of a new, unburdened, and final chapter in McConnell’s 40-year Senate career.

But then a funny thing happened: Pete Hegseth, a nominee who made up for his singular lack of qualifications with heaping doses of personal scandal, was confirmed anyway. Since that outcome was known by the time McConnell cast his vote, McConnell’s “no” vote wasn’t the highest of high dramas. (One thinks, instead, of John McCain voting down Obamacare repeal in 2017 as then-Leader McConnell stood nearby, arms folded, face down.) There weren’t gasps, and McConnell joined the rest of the chatty Senate floor by yukking it up with Texas Sen. Ted Cruz.

Coverage of McConnell’s vote has described it as a “shot across the bow,” or “a message” sent to Washington. “Mitch McConnell might not run the Senate anymore,” Politico described it, “but he made clear on Friday night that he still knows how to wield power.”

We’re sure McConnell hasn’t forgotten how to wield power. But the only practical effect of his “no” vote was to inconvenience the tiebreaking vote, Vice President J.D. Vance, on a Friday night. McConnell, who has unusually thick skin, is in the twilight of his career. Most of his fellow Senate Republicans are in the thick of theirs. McConnell’s vote may be liberated, but the outcomes are out of his hands.

The most surprising thing about McConnell’s Hegseth vote was that he didn’t try to block the nomination earlier, on one of the procedural votes preceding confirmation. On the merits of his decision, though, McConnell has been open and direct about his priorities for his final two years in office. Secretary of Defense Pete Hegseth didn’t fit into them.

Mitch McConnell is a traditional Republican defense hawk. In speeches, press conferences, interviews, and articles over the past year, he has been explicit in saying that his focus is on repelling—or at least slowing down—the “isolationist” elements overtaking his party. He believes that the United States is under a concerted attack from Russia, China, Iran, and their proxies “to undermine the U.S.-led order that has underpinned Western peace and prosperity for nearly a century,” and has argued that the global situation is as “dangerous” as it has been since the period before World War II. To counter this, McConnell has called for substantial increases in defense spending and “hard power.” He intends to see that through himself. When McConnell stepped down as leader, he had pick of the litter over committee assignments. He chose the defense subcommittee gavel on the Appropriations Committee.

And so Pete Hegseth, who was poached from a career in weekend television hosting, didn’t strike McConnell as the sturdiest partner in this endeavor. In a lengthy, scathing statement following the vote, McConnell reiterated his view of the grave threats facing America, and why Republicans needed better than the nominee placed before them.

“Mere desire to be a ‘change agent’ is not enough to fill these shoes,” McConnell said. “And ‘dust on boots’ fails even to distinguish this nominee from multiple predecessors of the last decade.” He hit Hegseth for failing to offer “substantial observations on how to defend Taiwan or the Philippines against a Chinese attack, or even whether he believes the United States should do so. He failed, for that matter, to articulate in any detail a strategic vision for dealing with the gravest long-term threat emanating from the PRC.” And, in a dig at Hegseth’s past bravado against women in combat, he said, “The restoration of ‘warrior culture’ will not come from trading one set of culture warriors for another.”

McConnell’s explanation—whether or not you agree with his dour view of the world’s dangers and his proposed remedies—was untouched by politics. He didn’t even bother hedging about how the vote kept him up at night but that he could not in good conscience go along with it; there was no side puffery about how President Trump was God’s gift to the nation. He didn’t offer to make it up later. He just listed the reasons why the nominee was bad, and he said that he would vote against him.

No other Senate Republican has the luxury of being able to separate themself from politics so fully. Sure, it wasn’t entirely easy for Maine Sen. Susan Collins and Alaska Sen. Lisa Murkowski to join McConnell in voting against Hegseth. But those two Republicans, and those two specifically, have been reelected to the Senate with moderate coalitions to whom they have to tend. And Alaska’s nontraditional voting system insulates Murkowski from right-wing primary opponents, while Collins’ brand is strong enough to vanquish any opposition from her right.

So you’ve got McConnell, whose semiretirement and focus on legacy render him immune to the pressures of Trump or Kentuckians clamoring for Secretary of State Pete Hegseth to fire the generals who wear dresses. You’ve got Murkowski and Collins, whose political incentives guide them toward rejecting Trump’s most glaring excesses. You need one more Republican to vote down a nomination. Who’s that going to be?

Well?

It’s not going to be North Carolina Sen. Thom Tillis. Tillis had been wobbling in his support for Hegseth on the afternoon before the vote. You’d better believe that he came around. While Tillis holds one of the few seats Senate Democrats will be targeting in 2026, he first has to get through a Republican primary—and being the deciding vote to kill one of Trump’s first major nominees may well have nuked him.

Would any other of the remaining few Trump-cautious Senate Republicans like to nuke their Senate careers? Louisiana Sen. Bill Cassidy? Indiana Sen. Todd Young? Utah Sen. John Curtis? Maybe some or several of these senators are preserving their “no” votes for the nominee that terrifies them most, like Robert F. Kennedy Jr. or Tulsi Gabbard. But we’d venture that more than three Republican senators felt Hegseth’s nomination was a joke. Only three did anything about it.

These incentives make it hard for McConnell to play the role that Trump’s opponents would project onto him: the elder whose gravitas and sage counsel can move votes beyond his own to block Trump’s use of the Senate as a doormat. Whichever Senate Republican becomes that 51^st vote to kill a nomination immediately places a primary target on his or her back. Indeed, even having voted with Mitch McConnell, on its own terms, makes that target a little bigger.

It’s not clear what McConnell’s sage counsel would be, anyway. The senator has had a smattering of major policy interests over the years: a robust national defense, a conservative judiciary, and beating back any limits on the amount of money in politics. But his supreme interest has always been the engineering and maintenance of a Senate Republican majority. He may have nothing left to lose, but he’s not one to advise those who could lose plenty to risk it.

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