The Claremonters are thinkers and activists associated with the Claremont Institute, a think tank known for its scholars’ work on American founding principles and rooted in the scholarship of the philosopher Harry Jaffa, a student of Leo Strauss. Ms. Field emphasizes Claremont’s strong alignment with Donald Trump, which became evident with its publication of the essay “The Flight 93 Election” on Sept. 5, 2016. Michael Anton, then writing under the pseudonym Publius Decius Mus, criticized the current conservative movement and argued that voters must take control as the passengers did on the hijacked Flight 93 on Sept. 11, 2001, or face certain defeat. A Hillary Clinton presidency, in Mr. Anton’s view, was not a survivable event. He also warned that defeat was possible even if you took control. Mr. Trump might fail.