If there's any cliché more tired than the Nazi analogy, it might be the claim that making a Nazi analogy in a public debate automatically disqualifies your argument.

Known as Godwin's Law, this rule states that in any discussion, the probability of a Nazi analogy being made eventually reaches 1, provided the conversation continues indefinitely. Godwin's Law was originally merely descriptive. But nowadays, if you prove Godwin's Law true by invoking Hitler or the Nazis, your argument is suddenly viewed as ipso facto risible. That shouldn't be the case.

Let me immediately concede this point: Yes, people make all sorts of bad Nazi analogies all the time. Bad analogies are bad, and bad analogies should always be derided as bad.

But not all Nazi analogies are bad. In fact, many Nazi analogies are a good part of public discourse.

Nazism is the single most awful ideology ever vomited out of the bowels of our pestilential human history. With its racism, its genocidal mania, and its apocalyptically relentless violence, Nazism remains a unique distillation of human evil, the devil's masterpiece.

It makes perfect sense that the most totemic example of evil in human history would get a lot more mentions than the various runners-up. When we try to give examples of goodness, we evoke Mother Teresa and Gandhi, not sort-of-nice chaps.

What's more, the totemic nature and frequent invoking of Nazism ensures that its firm status as the greatest evil ever is reinforced. Given the alarming rise of anti-Semitism in many parts of the world, the fact that there can be little doubt about polite society's revulsion toward Nazism is reassuring.

And here's another reason Nazi analogies aren't always bad: Some things actually are like Nazism.

The 1938 Munich debacle really is an example of what happens when the civilized world puts cowardice ahead of principle, and a cautionary tale of the dangers — and immorality — of appeasement. Does that mean we need to let slip the dogs of war whenever a tin-pot dictator blows his nose? Of course not. But Munich was not a sui generis event, and to a priori dismiss any comparison of any situation to Munich as faulty simply because it's compared to Munich is ridiculous.

For example, Stalin's blockade of West Berlin was clearly a "Munich moment" — a moment of truth in which a totalitarian leader made clear his intent to grab as much of the world as he could, and in which civilized nations could either stand firm or invite a domino effect; and one can't help but think that the freshness of the memory of 1938 steeled the West's resolve.

Similarly, it's hard not to think of the Nazi program of eugenics and Nazism's deranged view of the perfectibility of human nature when one reads the works of people like Joseph Fletcher, hailed as a "pioneer of medical ethics" in his New York Times obituary, who openly advocated the forced sterilization of the "unfit" and abortion of "defective" pregnancies.
Some things are like Nazism, or remind us of Nazism, even if they are not exactly Nazism.

Again — bad analogies are bad. But not all Nazi analogies are bad analogies. And a wholesale ban on Hitler comparisons doesn't do the world any favors.

And if you disagree, it must mean you're worse than Hitler.