An Illinous man attacked unarmed Republicans at their charity baseball practice and wounded some of them before being killed by two officers from one of the victim's security detail. (Thank God no one was killed except the shooter) This incident could be linked to the second amendment, the right to bear arms, because the shooter, as a citizen, had the right to carry a firearm. He didn't, however, have the right to shoot people just because they were Republican.
President Trump tweeting so much could also be linked to the first amendment, the freedom of speech. He can lawfully say whatever he wants, even covfefe. ;)