Trump campaign says former president is safe following possible gunshots in his vicinity. The Secret Service, in conjunction with the Palm Beach County Sherriff's Office, said it is investigating a protective incident involving Trump.
If you look up the guy's (now deleted) twitter, the guy was a pro-NATO nutcase who I guess earnestly believed Trump would disband NATO.
I'm not calling all people who are pro-NATO nutcases, I mean the dude was mentally ill and extremely pro NATO, claimed he had thousands of "NATO-trained Afghan troops" ready to defend Taiwan, claimed he was going to go fight in Ukraine, tried to buy a rocket from Elon Musk to assassinate Putin, etc.
He also claimed the purpose of the threat was to strengthen NATO by getting more countries to increase their military budgets. Trump isn't anti-imperialist.