On May 16th, Louisiana Republican voters handed Senator Bill Cassidy his walking papers. He finished third in his own primary — behind two challengers, one of them backed by President Trump — becoming the first sitting Republican senator to lose renomination in nearly a decade. His political career, for all practical purposes, is over.

Four days later, he voted to advance a War Powers Resolution designed to strip President Trump of his authority to conduct military operations against Iran.

Let that sequence sink in for a moment.

The resolution, sponsored by Democratic Sen. Tim Kaine of Virginia, would direct the president to remove U.S. Armed Forces from hostilities against Iran unless Congress explicitly authorized the action through a formal declaration of war or a specific Authorization for Use of Military Force. The Senate advanced it 50-47 — the first time in eight attempts that Democrats managed to push it through procedural hurdles. All seven previous tries failed.

What changed on the eighth attempt? Bill Cassidy decided he had nothing left to lose.

Cassidy joins the usual Republican suspects in this particular hall of shame. Susan Collins of Maine voted yes. Lisa Murkowski of Alaska voted yes. Both have made careers out of being the Republicans Democrats call when they need a headline. Their votes were about as surprising as a rainstorm in Seattle.

Rand Paul also voted yes — though Paul's reasoning is at least principled. He's been a consistent voice against undeclared wars and executive overreach on military authority going back years, regardless of which party holds the White House. You can disagree with him, but he's not doing this out of spite. The man has a philosophy and he sticks to it. That's more than you can say for the others.

Cassidy's vote is something different entirely. This is a man who voted to convict Donald Trump during the second impeachment trial, watched his own constituents punish him for it in poll after poll for five years, and then just confirmed what Louisiana Republicans already knew about him. He's not a statesman making a principled stand. He's a lame duck firing one last shot through the window on his way out the door.

Here's what's worth understanding about the resolution itself: it's not going to become law. It still needs to pass a final Senate vote. It would need to clear the House. And even if it somehow did all of that, Trump would veto it, and there are nowhere near enough votes to override. This was a messaging exercise dressed up as legislation — and Cassidy handed Democrats the vote they needed to run the message.

For what it's worth, at least one Democrat understood the assignment. Sen. John Fetterman of Pennsylvania voted against advancing the resolution — making him the lone Democrat to cross the aisle in the opposite direction. Fetterman has been drifting toward common sense on national security issues for a while now. He may be the most honest person in his caucus, which is a strange thing to have to say about a man who shows up to Senate votes in cargo shorts.

The resolution is going nowhere. But the vote matters anyway — because it reveals exactly who these people are when accountability is removed.

Cassidy spent five years pretending he was a principled Republican making tough calls. What he actually was, it turns out, was a senator waiting for the moment he couldn't be punished anymore to show his hand. His constituents figured it out before he ever admitted it. They sent him home. And on the way out, he did exactly what everyone suspected he would.

The voters of Louisiana were right. They just should have done it sooner.