Sanders lost California, and he lost the nomination. And with each day that he withholds his endorsement, he loses a little more of the political capital he gained during the primaries. Sanders undoubtedly shifted the balance of power in the Democratic Party and exposed its generational future. But his personal involvement in these changes is quickly fading.

History is full of examples of candidates who ran thrilling primary races, came up short, and then translated that excitement into tangible gains: a key cabinet post (Clinton), a future candidacy (Ronald Reagan, Gary Hart), or influence in the next administration through personnel appointments or policy commitments.

Sanders could have ranked among them. But, for reasons rooted in his personality and aloof political style, it looks like he won’t. He’s trapped by an inability, baffling even to some of his supporters, to end his campaign on advantageous terms. For weeks he’s swerved like a loose fire hose between gruff suggestions of support for Clinton—saying he’ll do all he can to stop Donald Trump—and threats to keep fighting her straight through the convention, possibly expecting she’d be indicted for maintaining a private e-mail server as secretary of state. (On July 6, the day after the FBI said it wouldn’t recommend any charges, the Department of Justice said none would be pressed.)