Russian President Putin has now openly pledged to defend Russian territory with "all the forces and means at our disposal." U.S. President Biden has responded that Russia will suffer "catastrophic consequences" if it resorts to the use of nuclear weapons. 

As Putin has correctly pointed out, it is the U.S. government that has established the precedent for the wartime use of nuclear weapons. That, of course, was the U.S. atomic bombings of the Japanese cities of Hiroshima and Nagasaki in World War II.

Let's review the justification that U.S. officials cite for targeting those two cities with nuclear bombs. 

U.S. officials, as well as many of their supporters in the mainstream press, have long maintained that the U.S. government was justified in nuking those two cities because, they say, it shortened the war. In the process, they say that the bombings saved thousands of American men whose lives would have been lost if it had become necessary to invade Japan.

That, however, is an invalid legal and moral justification for nuking Hiroshima and Nagasaki. After all, it's a war crime for soldiers to target civilians in wartime. That's precisely what U.S. officials did with their atomic bombing of those two cities. There is no difference between, say, what Lt. William Calley did in Vietnam when he killed innocent civilians and what U.S. officials did to the people living in Hiroshima and Nagasaki. 

Moreover, soldiers die in war. That's the nature of war. To target women, children, seniors, and other civilians as a way to save soldiers from dying in an invasion is totally illegitimate.