Atavistic racism: greatest impediment
Racism, alas, exists in all societies. In Western Europe, racism is practiced by fringe minority social groups -- such as attacks by German skinheads against immigrant Turkish workers -- or as a reaction against the liberalism and the openness of mainstream society -- such as voter support for Jean-Marie Le Pen in France.
In the United States, even though the White House is now inhabited by what many consider a very rightwing president, there are blacks in his Cabinet and his rebuke to Trent Lott, the Republican senator from Mississippi, cost him his job as majority leader.
Japan has not reached this stage. Japan is an outlier; from the racism viewpoint, it is a pariah state. Racism lies in the very fabric of Japanese society; it is still at its primitive, visceral and atavistic stage. It is so ingrained that Japanese often appear totally bewildered when told they are racist. Being racist and being Japanese are so intertwined that racism is not seen as a form of deviance, but as normal. So Japanese racism is rarely expressed in vituperatively violent form. It is passive, intrinsic, underlying general social behavior. Barring foreigners from joining golf clubs, for example.
Let me skip a few decades back and recount two stories that occurred in Oxford when I was there in the late 1960s. Oxford landladies were notorious for not renting rooms to nonwhites. One of the students at my college, a Ghanaian -- who has since become a prominent official at the United Nations (not Kofi Annan!) -- kept being told over the phone that rooms were available, only to be turned down when he arrived at the door.
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The Oxford landladies and my friend's parents did not see themselves as racists. They would not be the kind to go out and burn crosses or engage in the skinhead pastime of "Paki-bashing" (beating up Pakistanis). They were caught in the social warp of the time. Like most Japanese today, their racism was one of exclusion due to suspicion of the unknown.