A California man was charged in federal court on Monday with allegedly seeking to kill President Donald Trump at a gala dinner in a Washington hotel on Saturday night. Cole Tomas Allen faces two other criminal charges in connection with the thwarted attack at the annual White House Correspondents’ Association dinner. To Mr. Trump’s supporters, the incident is more evidence of a rising tide of left-wing violence. They accuse Democratic leaders and members of the media who rail against the president of creating a permission structure for extremists. And while the link between rhetoric and action isn’t straightforward, political violence experts point to a recent uptick in left-wing extremist attacks after years in which far-right extremists posed a far more deadly threat to the public and to government officials. This uptick includes the killing of a health insurance chief executive in New York in December 2024 and the killing of Charlie Kirk, a right-wing commentator, on a Utah college campus last September.…