A Teacher Marched to the Capitol. When She Got Home, the Fight Began.

Kristine Hostetter was a beloved fourth-grade teacher. Then came the pandemic, the election and the Jan. 6 riot in Washington.

SAN CLEMENTE, Calif. — Word got around when Kristine Hostetter was spotted at a public mask-burning at the San Clemente pier, and when she appeared in a video sitting onstage as her husband spoke at a QAnon convention. People talked when she angrily accosted a family wearing masks near a local surfing spot, her granddaughter in tow. Even in San Clemente, a well-heeled redoubt of Southern California conservatism, Ms. Hostetter stood out for her vehement embrace of both the rebellion against Covid-19 restrictions and the stolen-election lies pushed by former President Donald J. Trump. This was, after all, a teacher so beloved that each summer parents jockeyed to get their children into her fourth-grade class. But it was not until Ms. Hostetter’s husband posted a video of her marching down Pennsylvania Avenue toward the Capitol on Jan. 6 that her politics collided with an opposite force gaining momentum in San Clemente: a growing number of left-leaning parents and students who, in the wake of the civil-rights protests set off by the police killing of George Floyd, decided they would no longer countenance the right-wing tilt of their neighbors and the racism they said was commonplace.