The news is full of debate about whether Vladimir Putin is like Adolf Hitler [“Hillary Clinton draws rebukes with comments comparing Putin, Hitler,” front page, March 6]. The analogy is off by about 25 years.

Today’s world features one aggressive power with limitless ambition, a large population and a burning desire to take its place in the sun. China is like Imperial Germany. The United States is like Great Britain in 1900, a nation that has controlled the world through its military and its trade networks but has wearied of being a global policeman and now is trying to trim its imperial overreach with a new defensive strategy. The third actor in this scenario is Russia, analogous not to Nazi Germany but to the Austro-Hungarian Empire: shamed by years of internal collapse, prey to a host of ethnic separatists and burning to avenge its wounded pride.

It has been a century since the Great War began, and the Second World War concluded 69 years ago. All the wars since then have been localized. The specter of “mutually assured destruction” has given us an uneasy peace. But the invention of tactical nuclear weapons in the 1980s has guaranteed that the 21st century will not be spared atomic warfare. As political philosopher Hannah Arendt might say, we are due for another Big One.

Unfortunately, the leaders of the world are mediocrities, lacking a vision of the future that is strong enough to work against this oncoming cataclysm. We can only hope that a sense of restraint will grow and spare us from a third World War in a century.

Richard Ashford, Chevy Chase

Hillary Rodham Clinton’s analogy to Adolf Hitler and the invasions of Poland and Czechoslovakia to “protect” German minorities is spot on.

Despite some isolationist sentiment, the U.S. response should have been strong and swift. For instance, the United States could have withdrawn all but a skeleton staff from its embassy in Moscow or restricted Russian diplomats from movement on U.S. soil. What the United States does in concert with other nations is wholly separate from what the United States can do alone. President Obama is only now beginning such measures. The onus should have been on Vladi­mir Putin to restore Russia’s standing, not the other way around.

Ronald Scheraga, Alexandria

It seems ironic that everyone, including the State Department, is talking about the importance of the pipelines carrying gas from Russia to Ukraine and other countries when the State Department cannot approve the Keystone XL pipeline.

Jack D. Hill, Rockville