A fanatical Republican broke into Nancy Pelosi's home, armed and planning to attack her. She was out, so he attacked her husband instead.

Republican leaders cannot fail to know that their barely veiled support for violence will inspire real attacks. That must be their intention.

I think it is a mistake to equate violent fanaticism with mental illness. Mental illness only rarely leads people to contemplate violence towards others. Violent political fanatics often do at least contemplate it.