Editor's note: Timothy Stanley is a historian and columnist for the Daily Telegraph. He is the author of the forthcoming "Citizen Hollywood: How the Collaboration between LA and DC Revolutionized American Politics"
(CNN) -- It's called Godwin's law. The longer a debate rages, the greater the likelihood that someone will compare someone else to Hitler.
And Hillary Clinton has done just that: On Tuesday the former secretary of state reportedly told a private fund-raising party that Russian President Vladimir Putin's actions are similar to Hitler's in the run up to World War II.
Her quote (according to the Long Beach Press-Telegram): "All the Germans that were ... the ethnic Germans, the Germans by ancestry who were in places like Czechoslovakia and Romania and other places, Hitler kept saying they're not being treated right. I must go and protect my people, and that's what's gotten everybody so nervous."
Of course, what also gets everybody "so nervous" is leading statesmen comparing Putin to Hitler and, thereby, raising the specter of another world war.
It's unlikely that Clinton intended to gain politically from these remarks -- and they were carefully qualified. She added that "there is no indication that Putin is as irrational" as the German dictator was. But they could indicate that if she wins the 2016 election, America might gain a slightly more forceful president in foreign affairs, someone more willing to engage directly in Europe than Obama has. You may recall that in the 2008 primaries she was the Democrats' hawk candidate -- so much so that Ann Coulter preferred her to John McCain (Coulter called her "our girl").
But was Clinton right? Mostly no. It is true that Putin's justification for intervention in Ukraine is similar to Hitler's, that is, threatening to invade a sovereign territory to defend his ethnic brethren. But the situation is complex, and the historical comparison is tenuous at best.
After all, in the eyes of many ethnic Russians, it is the Ukrainian nationalists -- not Putin -- who are the Nazis. The Russians have asserted, quite accurately, that the revolution that overthrew a pro-Russian, democratically elected leader has resulted in the elevation of Russophobe fascists into key government positions. For example, the new secretary of the Ukrainian National Security and Defense Council is Andriy Parubiy -- co-founder of the Neo-Nazi Social-National Party of Ukraine (SNPU).
Another creator of the SNPU is Oleh Tyahnybok, a high-profile leader of the Kiev protests who has blamed Ukraine's problems on a Jewish conspiracy run out of Moscow. Ukraine's new deputy secretary of national security is Dmytro Yarosh, leader of the Right Sector group, which regards Tyahnybok as a soft liberal and which flies the old flag of the Ukrainian Nazi collaborators at its rallies.
In other words, in this situation, who exactly are the Nazis? Putin's ethnic Russian nationalists? Or the fringe of the ethnic Ukrainian nationalists? Neither is particularly pleasant.
Of course, the Ukrainian Nazi movement is small, and Ukraine is dwarfed by Russia, which puts Putin in the role of the dominant regional power picking on a small country and exploiting its extremist politics for the purpose of propaganda. But Putin is still no Hitler, because he lacks the German Fuhrer's global vision.
Hitler worked by an all-encompassing racist ideology that dreamed of turning Europe into a giant living space for his people. Putin -- the leader of a democracy, albeit a highly corrupt and politically stagnant one -- simply meddles in the affairs of countries that could reasonably be said to fall within his country's historical sphere of influence. Ukraine was a part of the Soviet Union until two decades ago (whereas Crimea was part of Russia until 1954), the country contains millions of ethnic Russians and, crucially, it has Russian military installations that are key to Russia's strategic interests.
In other words, a Russian invasion of Ukraine is not going to be a stepping stone to the invasion of France. Unfortunately, it may well be a stepping stone to involvement in the affairs of the Baltic states -- which are firmly in NATO and the EU. This is why Putin's latest ambitions have to be checked.
Nevertheless, calling Putin Hitler is careless. Even reckless. As Marc Tracy points out in the New Republic, it's historically insensitive and ignores the tapestry of cultural clashes and political calculations going on. It smacks, too, of the Manichean division of the world between good and evil that permeated the war on terror and led to so many terrible mistakes and so many American deaths overseas. Worse, still, is that such provocative language should be applied to a confrontation with a state like Russia.
We are dealing with a major power with nuclear weapons that has the capacity to reduce the world to so much irradiated ash. The West needs to be careful with its words.
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The opinions expressed in this commentary are solely those of Timothy Stanley.