Statistics
But you might also want to take into consideration the population per square mile of those other countries. Not to mention that in those other countries, like Denmark, have socialist structured government that either finds jobs for the jobless or pays them handsomely for unimployment insurance, which is why their taxes are so darned high. Plus their prison terms are so much harsher.
And then there's all the burglaries that go unreported over there. Also, only handguns are outlawed without special permits in Denmark, Canada and Germany. I've been to those countries.....
Either way, the U.S. is the only country that has something called the 2nd Amendment, and we really don't give a hoot how those other countries bind their citizens with gun restrictions. That's them, this is us, and I have guns to prove it...