The assault-weapons ban left the political stage with a whimper this past week.

Senate Majority Leader Harry Reid, D-Nev., signaled the end Tuesday when he announced that the ban on assault weapons (as well as on high-capacity ammunition magazines) would be stripped from the gun bill and offered only as an amendment on the Senate floor. Reid added that the assault-weapons ban had only about 40 votes.

The news — while not entirely unexpected, given the fraught politics of gun measures for Democrats running for office in places such as South Dakota, Montana and Arkansas in 2014 — hit Sen. Dianne Feinstein, D-Calif., hard.

“I very much regret it,” she said of the near-certain defeat of the assault-weapons ban. “I tried my best, but my best, I guess, wasn’t good enough.”

For Feinstein, the defeat was personal. Her political career is scarred by gun violence; she became mayor of San Francisco after the 1978 assassinations of Mayor George Moscone and City Supervisor Harvey Milk.

After the murders of 20 children in Newtown, Conn., in December, Feinstein, who has long worked within the Senate to tighten gun-control laws, insisted that now was the time to reauthorize the assault-weapons ban that had expired in 2004, after a decade in effect. When she introduced the legislation in late January, she acknowledged the uphill fight to passage but added, addressing the public: “There is one great hope out there, and that is you. Because you are stronger than the gun lobby. You are stronger than gun manufacturers.”

But despite the fact that scads of polls show that a majority of Americans support an assault-weapons ban, the political will — yet again — isn’t there to get it passed.

Dianne Feinstein, for believing that politicians might put politics aside, you had the worst week in Washington. Congrats, or something.

• Chris Cillizza writes for The Washington Post.

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