Law is not the only variable and is not deterministic. Social environment and cultural values are of great influence.

The US media glorifies violence and yet censors the reality of it.

How many of those other countries with stricter gun control laws have been involved in as many violent conflicts across the globe as the US?

Excellent question. There can be many factors, among them: - base rate of violent crime in general being lower - lack of access to guns - higher vigilance of school teachers - more mixed rather than segregated environments - more parental oversight and awareness of issues with children - less stressful environment

> Also, how come the incidence of these types of shootings are so much lower in other parts of the world if there is no policy that will help prevent them?

Well, the short answer is that deaths from incidents like this are actually more common, considerably more common, in some other parts of the developed world[0]. The majority of U.S. mass shootings result in no deaths, the overwhelming majority result in one or fewer. Only about 70 of the 474 or so mass shootings in 2017 were also classifiable as "mass murders" (single incidents resulting in four or more unjustified killings).

[0]: http://www.politifact.com/truth-o-meter/statements/2015/jun/...