Kentucky's U.S. Rep. Thomas Massie said attacks from fellow Republican President Donald Trump show he's worried about congressional opposition.

President Donald Trump and his political operation are working to unseat their first Republican incumbent: Kentucky Rep. Thomas Massie, who has drawn Trump's wrath by saying the president lacked the authority to attack Iran's nuclear sites without congressional approval and voted against his massive tax and spending cuts

President Trump fired back at Massie via Truth Social, labeling the Kentucky lawmaker a “third-rate Congressman” and accusing him of being “very bad for the Constitution.”