From the 2016 US presidential election and into 2019, we demonstrate that a visceral feeling of oneness (that is, psychological fusion) with a political leader can fuel partisans’ willingness to actively participate in political violence. In studies 1 and 2, fusion with Donald Trump predicted Republicans’ willingness to violently persecute Muslims (over and above other established predictors). In study 3, relative deprivation increased fusion with Trump and, subsequently, willingness to violently challenge election results. In study 4, fusion with Trump increased after his election and predicted immigrant persecution over time. Further revealing its independent effects, this fusion with Trump predicted a willingness to persecute Iranians (independent of identification with him, study 5); a willingness to persecute immigrants (study 6); and a willingness to personally protect the US border from an immigrant caravan (study 7), even over and above fusion with the group of Trump’s followers. These findings echo past political movements and suggest critical future research.