Sorry, Trump can't do a damn thing about what goes on in the City of Chicago..
That is correct....the fed gov. can't send in troops...Chicago's problems are a city and state matter.
How to stop the killings (or at least most of them) would require the city to do something considered unconstitutional...stop and frisk. They could send in the National Guard, but that would require a continual presence.
Ninety plus percent of the shootings and killings in Chicago are in the black and Hispanic neighborhoods. I don't know how NYC did it, but even though S and P has been stopped in NYC, the homicide rate is almost one tenth of what it was in the early nineties before Giuliani took over. And NYC is more than twice the population of Chicago.
So when the pols and all the big libs say they have no cure for the violence, they're wrong. Do a stop and frisk in the black and Hispanic neighborhoods, and the homicide rates will drop.