Another way of looking at it is proximity to the United States, its massive supply of guns and "war on drugs", which somehow seems to be correlated to an increased homicide rate.
The homicide rate in Puerto Rico is super high, comparable to other news world countries, but it’s an island and has almost no guns.
Also, the US homicide rate was extremely high compared to Europe long before gun laws in other countries or the drug war. It was 10x higher than the UK at the turn of the 20th century.
