Given the tendency in Japan to blame criminal activity on foreigners or Zainichi Koreans (despite most crime in Japan being committed by the Japanese,) I think it would also be naive to assume xenophobia isn't a factor.

> (despite most crime in Japan being committed by the Japanese,)

There are a lot more Japanese in Japan than there are foreigners. Similarly, blacks in the US "only" commit a little under half of murders... but they are much much less than half of the population.

When I visited Japan, I noticed that public trash bins are extremely rare. I read later, that they were removed after that poison gas terrorist attack in the 1990s. The problem in European countries is the lack of integration. The USA have a long tradition to integrate immigrants and avoided those kind of ghettos. And today I read that during 2002 and 2016, toddlers killed more people than terrorists..

Heck diarrhea kills more; depression kills more. We talk less about clean water than stratospherically-unlikely events like winning the lottery, succeeding in Silicon Valley or being killed by terrorists.