Danny Cevallos is a CNN legal analyst and a personal injury and criminal defense attorney practicing in Pennsylvania and the U.S. Virgin Islands. Follow him on Twitter @CevallosLaw . The opinions expressed in this commentary are solely his.

(CNN) Last week, former Massachusetts Gov. Bill Weld, who is seeking to become the Libertarian Party's vice presidential candidate, compared Donald Trump's plan to remove some 11 million undocumented immigrants from the United States to Kristallnacht, the infamous "Night of the Broken Glass" in 1938, when anti-Semitic mobs spread across Germany, Austria and Czechoslovakia, burning homes and businesses and attacking and killing Jewish residents.

When CNN's Jake Tapper pushed back, asking if it was a "little strong" to make Holocaust comparisons, Weld engaged in a behavioral tradition used for millennia by politicians, defendants and generally anyone confronted with their own questionable choices.

He doubled down.

Instead of backing off or conceding any ground, he added more words to his original words.

No, Weld insisted, it was not too much. Specifically, he intimated that because he served on a Holocaust commission sometime in the 2000s, he was uniquely qualified to make Nazi comparisons.

Serving on a Holocaust commission is surely an honorable billet. It probably qualifies you to do and talk about a number of things. It does not bestow upon you a superior skill with Nazi analogies. In fact, the comparison game is dangerous whether you are a former Holocaust commission member, or just some angry guy on Facebook in mom's basement with a Wi-Fi signal.

It turns out Weld's remarks are an echo of the principle known as Godwin's law. I first heard about Godwin's law from another lawyer friend, the kind of guy who tells riveting tales, unencumbered by such inconveniences as certainty, or facts. But unlike his other inventive tales, he was right about Godwin's law; it was a real thing.

If nothing else, Godwin's law sounded important. Generally laws named after people are sound, scientifically proven, maybe even immutable. It's hard to dispute Newton's Laws of Motion, or Hubble's Law of cosmic expansion. Godwin's law is not exactly a hard science rule though. It is more a theory of Internet sociology, but one as predictable as the conclusions of Einstein or Heisenberg.

Godwin's Law of Nazi Analogies states : As an online discussion grows longer, the probability of a comparison involving Nazis or Hitler approaches one -- or a 100% probability.

Internet philosopher Mike Godwin wrote about his observations back in 1994 when most of us didn't even have an email address yet. Godwin's observations were brilliant and prescient. Even then he noticed that online discussions of all kinds eventually led to analogies to Hitler or Nazis: gun control and the Second Amendment ("Hitler banned weapons!"), birth-control debates ("It's genocide!") and censorship ("The Nazis burned books!").

Godwin's law went viral in a pre-viral era, without the aid of a Snapchat or Periscope. It holds true today, too. Lazy logic and ineffective arguments are now part of the effluvia of public speech -- online and otherwise. (We expect it from the Internet, but our politicians should be better at making their point than that.)

In general, arguing by simile is fraught with risk. Not everything is like the Holocaust. Not everything is like slavery, and not everything is like the Native American experience. If everyone compares their own, self-centered mission du jour to a present-day fight against Nazism, it eventually dilutes everyone's message and minimizes those events in history.

Photos: Trump campaign: 11 outrageous quotes Hide Caption 1 of 12 Photos: Trump campaign: 11 outrageous quotes Hide Caption 2 of 12 Photos: Trump campaign: 11 outrageous quotes Hide Caption 3 of 12 Photos: Trump campaign: 11 outrageous quotes Hide Caption 4 of 12 Photos: Trump campaign: 11 outrageous quotes Hide Caption 5 of 12 Photos: Trump campaign: 11 outrageous quotes Hide Caption 6 of 12 Photos: Trump campaign: 11 outrageous quotes Hide Caption 7 of 12 Photos: Trump campaign: 11 outrageous quotes Hide Caption 8 of 12 Photos: Trump campaign: 11 outrageous quotes Hide Caption 9 of 12 Photos: Trump campaign: 11 outrageous quotes Hide Caption 10 of 12 Photos: Trump campaign: 11 outrageous quotes Hide Caption 11 of 12 Photos: Trump campaign: 11 outrageous quotes Hide Caption 12 of 12

Trump's immigration plans understandably sound unconventional and extreme to many. Even Trump may think so. He's already indicated his willingness to back down on these controversial positions, saying his ban on Muslim immigration was a "suggestion." If Trump is so willing to change his views on immigration or walls, maybe -- just maybe, his opponents' Kristallnacht comparisons might be a little premature. And extreme. And not helpful to promoting a dialogue.

There are plenty of effective ways to argue with Trump. John Kasich did this well during the debates. He called Trump's immigration policy "silly" and quipped that if it weren't for immigration, Kasich would be running for president of Croatia.

Simple, even entertaining rhetoric. You can be an effective advocate against the toughest political foe without the improvident comparisons to genocide.

But maybe Weld's comments are just part of a new era of acceptable political discourse. After all, Twitter wars and genitalia jokes appear to have become part of public debate. Maybe there are no more rules to politics, and it's open season on comparing immigration policies to genocide or reviled Aryan ideologies. But when it comes to advocating your point of view, or even expressing a cogent idea, we can do better.