Trump threatens to back challenger to fellow Republican Boebert after she campaigns for Massie

WASHINGTON, May 16 (Reuters) - U.S. President Donald Trump threatened a primary challenge on ​Saturday for hardline conservative Representative Lauren Boebert, until now ‌a staunch Trump ally, after she campaigned for maverick Representative Thomas Massie in his Kentucky district. "Boebert is campaigning for the Worst 'Republican' Congressman ​in the History of our Country, Thomas Massie, of ​the Great Commonwealth of Kentucky, and anybody who can ⁠be that dumb deserves a good Primary fight!" Trump ​wrote on Truth Social. Boebert, a Colorado congresswoman, responded with a ​post on X: "Yes, I saw the President’s post. No, I’m not mad or offended....