It's a funny chart but it isn’t accurate. According to recent FBI statistics:
Vermont & New Hampshire have among the lowest gun violence rates, but they voted blue. Louisiana (especially New Orleans) has the highest gun violence rate, but it's a red state. Other areas in the chart aren't accurate either.
I’ve looked into this and I’ve found there is NO correlation between gun control laws and gun violence rates one way or the other. Here are a couple of other examples:
Chicago and NYC both have very restrictive gun control laws. Chicago is having an extraordinary high gun violence rate lately. New York City has been having the lowest gun violence rates its had for decades and it continues to decline.
The gun violence rate started to declined two years before the AWB was in effect between 1994 and 2004. After it lapsed in 2004 and ‘assault’ weapons became popular, the gun violence rate CONTINUED TO GO DOWN.
What the chart does show is a correlation between population density and gun violence. Personally I believe the crime rate has been going down because the boomers are getting older. Burglary & robbery is not an old man’s game.