You correctly highlight the magnifying link between the event and a wider “threat.” If Trump had a motive to go after mentally ill people he would be connecting individual criminal acts by unstable people with the “need to lock up people with mental problems.” That would change the story of one incident to a societal threat that a demagogue could exploit. It’s this connection between “this one bad thing” to “we’re all in danger” that drastically worsens the situation. — David Grace