Why isn't gun murder in USA cities a topic at the political debates?

Because Republicans don't want to go on the record supporting the gun massacres (even though they do). Remember when Jebby said "stuff happens" about the Umpqua school shooting? That didn't poll well for him.

Because the NRA and the GOP refuse to talk about it. It hurts the gun manufacture's profits.

It is. What planet are you on?

Maybe not the big debates, but gun violence, the causes, and the proposed solutions, are debated all the time at the local level.

Larger cities are overwhelmingly liberal. It's also where the majority of gun crime happens.

Because liberals are afraid that if it is brought up one of them might accidentally admit that not one law proposed by a Democrat would have had any impact at all on crimes where guns are used.

Murder is murder no matter what implement is used. Murders are handled by law enforcement. Why debate something we all agree on?

Because the NRA owns all the candidates and keeps them in line.

#Blacklivesmatter and the OWS movement are very focused on that-

The corporate media likes gun murder in US cities, it seems

Because the NRA is the most powerful special interest in US politics.

too much gun manufacturer money involved