You don’t even have to look to other countries to prove that gun control works. You just have to look at other states.

https://www.theatlantic.com/national/archive/2011/01/the-geography-of-gun-deaths/69354/

And what about gun control? As of July 29 of last year, Arizona became one of only three states that allows its citizens to carry concealed weapons without a permit. Might tighter gun control laws make a difference? Our analysis suggests that they do.

The map overlays the map of firearm deaths above with gun control restrictions by state. It highlights states which have one of three gun control restrictions in place - assault weapons’ bans, trigger locks, or safe storage requirements.

Firearm deaths are significantly lower in states with stricter gun control legislation. Though the sample sizes are small, we find substantial negative correlations between firearm deaths and states that ban assault weapons (-.45), require trigger locks (-.42), and mandate safe storage requirements for guns (-.48).

States with fewer guns have fewer gun deaths, on average.