Are you proposing that Henderson is safer than these large cities because there's less gun control, rather than other factors?
That said, the violence problems in Democrat-run cities is not because of the guns, nor is it due to gun regulation. There were a slew of poor governmental decisions that have led to massive inequality, poor social conditions, and fostered an us-vs-them culture through the militarizing of police and criminalizing of the poor.
It turns out that if people feel cornered with no way to improve their lives or escape their poor situation, they resort to organized crime or other desperate measures.
TLDR - Crime is primarily driven by social circumstances. Criminal culture is cultivated generationally by those circumstances.