As America and Iran are potentially poised on the edge of war, the cautionary words of one old soldier are worth recalling. Soldiers tend not to be peaceniks, but they do tend to be realists—and oftentimes, a realistic assessment of a hot and perilous situation is enough to engender a cool and peaceful solution.

With that in mind, meet Fox Conner (1874–1951).

Interestingly, Robert Gates, the former defense secretary, has already met him. Back in 2008, Gates published the essay “Reflections on Leadership,” in Parameters, the Army War College quarterly. In it he praised Conner, an obscure but profoundly consequential American military man, who mentored both Dwight Eisenhower and George Marshall, and whose influence echoes to this day:

From Conner, Marshall and Eisenhower learned much about leadership and the conduct of war. Conner had three principles of war for a democracy that he imparted to Eisenhower and Marshall. They were:

Never fight unless you have to.

Never fight alone.

And never fight for long.

In Conner’s “three principles,” we might recognize elements of the Weinberger Doctrine, enunciated in a 1984 speech by Ronald Reagan’s secretary of defense, Caspar Weinberger. General Colin Powell, a few years later, became associated with a similarly themed credo, the Powell Doctrine.

In his essay, Gates described Conner as “a tutor and mentor to both Eisenhower and Marshall.” Eisenhower, of course, was the war-winning general who went on, as commander in chief, to lead America to eight years of peace and prosperity. Marshall, who was Ike’s superior during World War II, served as secretary of state from 1947 to 1949 and oversaw the rebuilding of Europe, for which he was later awarded the Nobel Peace Prize.

So while neither Eisenhower nor Marshall were pacifists, they often concluded, in their realism, that peace was preferable to war. Maybe we need more of that sort of thinking in Washington today, including inside the Pentagon. 

So who was this Fox Conner? Born in Slate Springs, Mississippi, he was the son of a Confederate officer who had been shot in the head and blinded at the Battle of Atlanta during the Civil War. After the conflict, Robert Conner, now nicknamed “Blind Bob,” became a teacher and a successful trader of cotton, the quality of which he learned to judge by a sense of touch. It’s easy to imagine that the younger Conner, watching his father overcome a handicap, learned early on the value of finding varying strategies to accomplish desired ends.

Conner graduated from West Point in 1898, served under General John Pershing in World War I, and retired as a major general in 1938. Yet most notably, during his four decades in the Army and even after, he helped shape the careers and outlooks of Eisenhower and Marshall, as well as, interestingly enough, George Patton.

Hence the title of an admiring 2010 monograph by Army veteran and former West Point professor Edward Cox, Grey Eminence: Fox Conner and the Art of Mentorship. As Cox writes, Conner took Eisenhower, 16 years his junior, under his wing when they were both stationed in the Panama Canal Zone in the early 1920s:

After a long day’s work, Conner and Ike would read biographies of Civil War generals and spend long hours discussing their decisions. Frequently their conversations would continue after dinner long into the night. Conner assigned the writings of the Prussian theorist Carl von Clausewitz, still a military staple, on three separate occasions. Each time he would question Ike about the meanings and conclusions of Clausewitz’s seminal work, On War.

Yet Conner had more on his mind than just the strategy of war; he also wanted to teach Ike about the necessary context for a successful war:

Conner would often talk about the signing ceremony of the Treaty of Versailles. …[He] was convinced that the structure of the treaty ending World War I all but guaranteed another war. He theorized that it would happen within a quarter century, and he presciently understood that the next war would be fought, as the last one had, with allies.

Thus Conner hammered the point that a country needs allies: “Having seen firsthand the difficulties that allied warfare posed in his time on Pershing’s staff, Conner was determined to pass on the lessons he had learned.”

At the end of their time together, in 1924, Conner’s official evaluation rated his subordinate as “one of the most capable, efficient, and loyal officers I have ever met.”

The warm Conner-Eisenhower relationship continued over the coming decades, even past Conner’s retirement. And sure enough, during that next war which Conner had predicted, on July 4, 1942, Eisenhower wrote to his old teacher:

More and more in the last few days my mind has turned back to you and to the days when I was privileged to serve intimately under your wise counsel and leadership. I cannot tell you how much I would appreciate, at this moment, an opportunity for an hour’s discussion with you on problems that constantly beset me.

By then, Ike was in London, commanding Allied forces in Europe, soon to gain his third star—to be followed, of course, by a fourth and a fifth star. As commander, Ike knew how to move armies around, and yet, just as importantly, he was also a master diplomat and negotiator, dealing with the likes of Churchill and de Gaulle.

We’ll never know what would have happened to the U.S. if we had somehow fought World War II without allies, or with only weak alliances—but happily, we never had to find out.

Many years later, Eisenhower said of Conner, “In sheer ability and character, he was the outstanding soldier of my time.” For his part, Marshall “would maintain that he owed his greatest debts to the lessons he learned from Fox Conner.” Fittingly, in the conclusion to his monograph Cox writes, “Today it is time for a new generation of leaders to learn from and follow Conner’s example.”

In this spirit, nearly 70 years after his death, and with America moving closer toward war, perhaps we all should revisit those three key “Conner Principles”: never fight unless you have to. Never fight alone. Never fight for long.

We can quickly observe that the Confederate States of America, for which Conner’s father had fought, had violated all three of these principles: it fought a war of secession that it didn’t have to fight; it fought alone (no European country was going to join with a slave-holding society); and it fought for too long (30 percent of Southern white men, aged 18–40, died in the war).

Thus we might surmise that Conner incorporated life lessons, learned from his own Lost Cause background, into the formulation of larger, timeless pearls—about the need for good judgment in launching a conflict, about the need for equally good judgment in managing alliances, and about the need for a realistic vision of victory.

Now to the U.S. and Iran in 2020. Is the Trump administration keeping the Conner Principles in mind? For instance, how many countries are on our side? And if we don’t have allies, and an effective alliance, can we realistically expect to succeed in a military campaign? Just as importantly, can we succeed diplomatically and strategically?

Yes, of course, we can bomb Iran for a while, but we bombed North Vietnam for a long time too—and still failed. The lesson is this: if the foe has more patience and durability than we have, the foe wins. In Bruce Springsteen’s “Born in the USA”—that 1984 song whose melody sounds like an anthem, but whose lyrics are, in fact, a dirge—Springsteen describes this simple reality:

I had a brother at Khe Sanh fighting off the Viet Cong

They’re still there, he’s all gone …

Yes, they’re still there in Vietnam, and the U.S. is gone. Could that soon be said as well of any ambitious U.S. military action against Iran? Could it be that in a few years, after all the explosions and body bags and trillions in wasted treasure, there’s no evidence that we accomplished anything—only gaping craters, lost lives, and squandered resources?

So we come back to the wisdom of the Conner Principles: are we fighting a war we don’t have to fight? Are we fighting alone? Are we fighting forever? That is, are we fighting, as Donald Trump himself has railed against in the past, a “forever war”?  

If we can’t answer those questions satisfactorily, then maybe we shouldn’t be fighting at all.

As we have seen, Conner was no pacifist, and neither were his famous pupils. Yet depending on the situation, those realists, Eisenhower and Marshall, sometimes opted for peace, not war.

So now today, a Connerian analysis of Iran leads to a judgment—against war.