“And yet to reach for examples from the Holocaust, or the Jewish diaspora, has become a natural reflex when the question of ethnic or religious minorities comes up. It is a moral yardstick, yet at the same time an evasion. To be reminded of past crimes, of negligence or complicity, is never a bad thing. But it can confuse the issues at hand, or worse, bring all discussion to a halt by tarring opponents with the brush of mass murder.”