"In a pluralistic society a fundamental assumption of public policy is the recognition that everything immoral need not be declared illegal. The public morality that is expressed in law reflects a consensus derived from public debate. ... Social realities as well as religious principles must be taken into account in judging the wisdom of any legislation. Citizens who come to different conclusions are not necessarily immoral or unchristian. The tendency to so brand one's political opponents suggests a kind of moral facism." (Originally published in an editorial in America on September 13, 1980; recently republished in Liberty, Sept-Oct 2009.)
This came to mind as I have observed recent political debate.