He [a former Nazi party bill collector] asked me whether I had known anybody connected with the West Coast deportation. When I said "no," he asked me what I had done about it. When I said "Nothing," he said, triumphantly, "There. You learned about all these things openly, through your government and your press. We did not learn through ours. As in your case, nothing was required of us--in our case, not even knowledge. You knew about things you thought were wrong -- you did think it was wrong, didn't you, Herr Professor?" "Yes." "So. You did nothing. So it is everywhere." When I protested that the Japanese-descended Americans had not been treated like the Jews, he said, "And if they had been -- what then? Do you not se that the idea of doing something or doing nothing is in either case the same?"
On the one hand, not doing anything in the face of a moderate injustice is not as bad as not doing anything in the face of a serious injustice, which in turn is not as bad as doing nothing during a grave injustice. On the other hand, the rationalizing procedures we use to justify our inaction remain roughly the same throughout. So when we let moderate injustices slide by, it is highly indicative that we would do the same even if the sin committed were far more shocking.
In other words, the average American's indifference toward Japanese Internment is not, morally, equivilant to German indifference toward the Holocaust. But it is strong evidence that, if our policy toward the Japanese was one of extermination rather than internment, we'd have not protested then either.
I'm not even sure I believe that. I think values count for something, and I think that America has a sufficiently strong tradition (at least by 1942) of not sanctioning random killing in its own borders such that such a move would not be tolerated. But yet, counter-examples abound--lynch mobs, genocide of Native Americans, even the fire-bombing of Dresden or the nuking of Hiroshima and Nagasaki all indicate that our respect for the human life of non-combatant "others" was severely deficient.
Food for thought, anyway.