Russian President Vladimir Putin’s invasion of the sovereign nation of Ukraine under several pretexts reminds me of Adolf Hitler’s rationale for invading and annexing Sudetenland in 1938 and his invasion of Czechoslovakia and Poland a year later. Then, as now, the excuse was that German-speaking people (then) and Russian-speaking people (now) wanted to be part of Germany (then) and Mother Russia (now).

In both cases the excuses for invasion, occupation and murder were just that — excuses. Some commentators say there has been nothing like Putin’s invasion of Ukraine since World War II. There are dwindling numbers of people alive who lived through that period and witnessed the evil of Nazi brutality and genocide.

Ronald Reagan lived through that era. This is why he coined the phrase “evil empire” to describe the Soviet Union. It’s one thing to read about evil in history books, but it is quite another to have witnessed it. One need only listen to Holocaust survivors for a powerful lesson in how deep human depravity can sink if it is not opposed.

One of the definitions of evil is “The force in nature that governs and gives rise to wickedness and sin.” In our age of moral relativity where nearly everything is tolerated and justified — except people who oppose the new societal norms — who speaks of wickedness and sin? It’s getting harder to find preachers known for sermons on the subject.

Albert Einstein, who was German and Jewish, and who lived through that dark period of mass slaughter, was right when he observed: “The world is a dangerous place to live, not because of the people who are evil, but because of the people who don’t do anything about it.”

As with a serious disease, early detection is the best path to treatment and a possible cure. Though there is no immediate “cure” for evil, free nations can control its spread.

It’s worth revisiting Reagan’s evil empire speech to the British House of Commons on June 8, 1982. Reagan’s observations about evil were profound. While his references were to the Soviet Union and repressive regimes everywhere, his words equally apply to that regime’s ideological heir, Vladimir Putin and other dictators.

Reagan said: “If history teaches anything, it teaches self-delusion in the face of unpleasant facts is folly.” This was British Prime Minister Neville Chamberlain’s folly when he declared “peace in our time” after meeting with Adolf Hitler in Munich and believing Hitler’s promise not to seize more territory.

While Reagan’s policy of “peace through strength” worked, he told the Commons that military power was only part of the mix: “Our military strength is a prerequisite to peace, but let it be clear we maintain this strength in the hope it will never be used, for the ultimate determinant in the struggle that’s now going on in the world will not be bombs and rockets but a test of wills and ideas, a trial of spiritual resolve, the values we hold, the beliefs we cherish, the ideals to which we are dedicated.”

World War II came about in part, said Reagan, because the West allowed “dictators to underestimate us.” Now we see the reverse. The Biden administration is underestimating our enemies and projecting weakness. They think they can negotiate with the likes of Putin, China’s Xi and Iran’s ayatollahs when the only thing these and other dictators understand is power, resolve and resistance.

Learn that lesson and the world becomes a safer place. Failure to learn it produces what we are witnessing in Ukraine and may soon see in Taiwan, not to mention in an Iran equipped with nuclear weapons and a religious rationale for using them.

Readers may email Cal Thomas at tcaeditors@tribpub.com. Look for Cal Thomas’ latest book “America’s Expiration Date: The Fall of Empires and Superpowers and the Future of the United States” (HarperCollins/Zondervan).