There is no swatting problems in other countries because they don’t have SWAT! :)
But seriously, the heavily militarized police is a US only phenomenon.
France even has a national police force, the Gendarmerie, that is literally a branch of the military. The Gendarmerie’s most famous tactical unit is the GIGN, who have responded to high profile incidents including the 2015 terrorist attacks in and around Paris.
It's absolutely not a U.S. only phenomenon.
You know, innocent victims and all that.
Sounds stupid in that case, but I believe they did the maths properly when balancing the chance of armed illiterate young men in public killing innocents versus saving the day.