Not sure what this instances views on "advocating violence" are, so I'm trying to explain it as non-violently as I still can:
Americans want gun control. That's not up for discussion. It's an absurd majority.
However, as long as it is "only" school children and ordinary civilians dying, Republicans will not change their stance on gun control in the slightest. The people who are responsible to fix this are the only group that is not at any risk of getting shot. They are so absurdly protected that they will never be on the receiving end of a barrel, and therefore, do not care.
And to make matters worse, the Republicans dictating the supreme court, who will block anything that could possible address this problem, not only cannot be voted out, no, they literally have to die before they can be replaced.
The only people who could fix the gun murder issue are the ones not dying because of guns.