I have never witnessed this. I have no idea what I would do.

Its important to consider the fact I think society is insane and people are volatile.
I did step in and rescue my daughter when her old boyfriend became mentally abusive towards her.
I did set the rules of conduct concerning how her husband treats her.
I did teach my children not to abuse others.

I realized early in the pandemic that stress from the pandemic will make people fly out of control a bit faster. I talked with my children and their spouses and reminded them about having self-control and reminded them love, not hate is why they are with each other.

It does help that I'm not a violent man quick to losing my control and that bleeds off on my children.
I'm not ill prepared, I too carry a 'beater' in my truck. A 40" steel pinchbar. But, I don't put my nose where it doesn't belong.