It is a blinking man made tragedy.
For those who are interested in some comparitive facts on gun ownership and mass shootings between here in the UK and some other Western World Countries here is a link to a very interesting article written by a criminologist from George Washington University.
Despite intentional homicide rates decreasing by 40 - 50% in all 11 countries mentioned, mass shootings in the USA have increased massively in the same period and the association between gun ownership and mass shootings is high.
I dispute that it is easy to get and own an assault rifle here in the UK...although, of course, if you mix with a criminal sub culture who deals in guns, it is always possible. There isn't really an appetite for gun ownership here and I hope there never is.
In the decades that I prosecuted criminals I only once, despite dealing with several murders, prosecuted some for actually using a gun, and that was a shotgun used by a farmer pursuit of a fox, missing and hitting a chap on the side of the main road.
There were a few armed robberies where sawn off shotguns were carried but not used. Even those were very rare.