As for the shooter: Routh has a long history of making political statements on X. He appears to have previously supported Trump before moving towards the Democrats. In a self-published book about the Ukraine War, he wrote about visiting the country and becoming disillusioned with its chances of defeating Russia. At that time, he worked with Ukraine's International Volunteer Center to recruit U.S.-trained Afghan fighters to join the effort. In the book, he described Trump as an "idiot" and a "buffoon."

He repeatedly posted on X in support of President Joe Biden and Vice President Kamala Harris, claiming that "democracy is on the ballot." In June of 2020, he reflected on his former support for Trump, writing: "While you were my choice in 2106 [sic], I and the world hoped that president Trump would be different and better than the candidate, but we all were greatly disappointment and it seems you are getting worse and devolving. I will be glad when you gone."

Routh apparently visited the nation's capital last year to advocate on Ukraine's behalf. The New York Times interviewed him while he was in the city, and he posted a picture of himself in front of the Capitol on LinkedIn.