"It's easier to get into something than to get out of it."

The Trump administration finds itself in the unhappiest of positions, with no good options.

Throughout history, people who tried to warn about the dangers of war—to point out all of the terrible and unforeseen consequences of it—have been attacked as lacking patriotism and undermining morale.

Based on my study of history, the opposite is the reality. Those who caution against war are guys who wanted save their country from experiencing needless disaster and its mother and fathers from losing their young sons. My great grandmother lost her only son (my great uncle) fighting the Germans in Italy in World War II, and she never got over it. She once told my mother that the pain of it never really diminished.

Recently I’ve been astonished to receive messages from readers, advising me to consider that even President Madison—who considered war the greatest evil that could possibly befall a Constitutional Republic—requested that Congress declare war against Algiers in 1815 in what came to be known as the Second Barbary War.

Dear readers, my father was in the Marine Corps and I grew up hearing about the lore of brave exploits on “the shores of Tripoli.” Madison advocated this war because U.S. shipping was being attacked by pirates in the Mediterranean—pirates who kidnapped American sailors and held them for ransom. Of course Madison advocated sending the Navy to blast the pirates. It was the ONLY rational course of action.

There is a world of difference between deciding to use naval power to protect shipping, and the decision to attack a sovereign nation on the grounds that it poses a theoretical threat. I was under the impression that the people of this country had learned this lesson from President George W. Bush’s decision to wage preemptive war against Iraq. Apparently they didn’t.

Going back to the earliest stories and histories of warfare in the West—Homer’s Iliad and the histories of the Persian and Peloponnesian wars by Herodotus and Thucydides—we are taught the lesson again and again about ruinous consequences of prideful warlords who overestimate their power, and make overly optimistic assumptions about their chances for a rapid victory.

Donald Rumsfeld once remarked that “It’s easier to get into something than to get out of it”—a simple but true observation that he himself ignored when it came to Iraq.

Now President Trump finds himself having to learn this lesson again, though this time the mess he has made is on a global scale.

John Mearsheimer graduated from the U.S. Military Academy at West Point in 1970. He then served five years as an officer in the U.S. Air Force, during which he earned an MA in International Relations from the University of Southern California in 1974. He later earned a Ph.D. from Cornell University in 1980. Since 1982, he has been the R. Wendell Harrison Distinguished Service Professor of Political Science at the University of Chicago.

War is an extremely unpredictable thing, and it’s possible that Professor Mearsheimer is being excessively pessimistic. I fear that he is not, because days before I listened to this interview, I developed the exact same misgivings.