Say there was a politician named Joe America.

One of his millions of supporters, Bob Angry, has serious anger issues among other faults.

One day, Bob Angry blows up at once of Joe's enemies, calling him a string of cuss words.

PAUSE THE VIDEO.

Ask yourself, query your feelings -- how does this make you feel about Joe America?
1. Positive
2. Neutral
3. Negative

If you answered 3), you are a brainwashed fool.

What leader or politician gets to gatekeep who "gets to be" a supporter and who doesn't?

Now unless the politician himself acted similarly, or actively applauded such behavior, or condoned it, there isn't ANY reason to lose even 0.0001% of your respect for Joe America, even if one of his "supporters" does something much worse like blow up a church, or shoot up a movie theater.

You just can't blame a leader for the actions of his underlings unless you can establish a direct cause -> effect relationship.

Now say Joe America said, "We shouldn't put up with our enemies' crap any longer! Let's stop being civil to them!" and next week one of his supporters gets in a fight (or worse) with one of the aforementioned "enemies", then YES Joe would be guilty of inciting his followers to violence.