This article originally appeared at written by Mark Perry

Late on the afternoon of July 28, 1965, Gen. Harold K. Johnson, the then-Army chief of staff, arrived outside the White House in a limousine reserved for the use of members of the Joint Chiefs of Staff. According to an account that he gave to a group of Vietnam veterans many years later, he sat in the limousine for many minutes after removing the two sets of four stars from the shoulders of his uniform. He was pondering whether he should go through with it—whether he should put the stars he held in his palm on the president’s desk. Whether he should resign his position as the Army’s senior officer.

Just hours before the general’s White House arrival, his boss, President Lyndon Johnson, had told the nation that the United States was sending 50,000 troops to Vietnam and that more would be sent as required. The announcement stunned the general, because the president had earlier made a personal pledge to the Joint Chiefs that he would commit the full power of the U.S. military for the conflict, calling up the U.S. Army Reserve and a full six combat divisions, to help wage the new war. Calling up the Army Reserve was more than just a matter of numbers; it would have sent an unmistakable signal to the American people that the United States was going to war in Vietnam—that it would “get in, win, and get out,” in the words of General Johnson’s colleague and respected Vietnam commander, Gen. Bruce Palmer. Instead, the president had committed America to an incremental, tangential and surreptitious military buildup. It was, the army chief felt, a prescription for defeat.

Remembering the incident later, General Johnson acknowledged that after many minutes of reflection he reattached the stars to his shoulders—doing what any good soldier would do. He had his orders and he would carry them out. But he regretted the decision: “I should have taken off my stars,” he later told a colleague. “I should have resigned. It was the worst, the most immoral decision I’ve ever made.”

Chuck Hagel is not Harold K. Johnson, and the fight against the Islamic State is not Vietnam. And yet, the news of Hagel’s resignation on Monday is a distinct echo of that July day in 1965—one particularly resonant for Hagel, who began to question U.S. involvement in Vietnam after having served in an infantry unit there in 1967 and 1968—the war’s bloodiest years. “As a United States senator, when we talk of going to war against Iraq or against anyone, we need to think it through carefully,” Hagel told Politico in the run-up to his appointment as defense secretary in 2013. “This old infantry sergeant thinks about when I was in Vietnam in 1968, United States senators making decisions that affected my life and a lot of people who lost their lives, that they didn’t have, I didn’t have, anything to say about. Someone needs to represent that perspective in our government as well.”

It was his experience in Vietnam that might well have been on Hagel’s mind when he wrote a two-page memo on the U.S. policy on Syria and the fight against ISIL, addressed to the head of the National Security Council, Susan Rice, at the end of October. The memo, described in a New York Times article on October 29, was “sharply critical” of the White House “because of its failure to clarify its intentions toward President Bashar al-Assad.” In fact, a currently serving U.S. military officer told me in the wake of Hagel’s resignation, the soon-to-be-former secretary of defense was “not so much criticizing White House policy as he was criticizing the lack of one.”

At the heart of the Rice memo was Hagel’s concern that the administration’s failure to state its intentions toward Assad would undermine and unravel its entire Syria policy. Hagel was also uncomfortable with the administration’s insistence that it wouldn’t send ground troops back to Iraq. He thought that closed off an important option for the United States in case the ISIL threat grew. It’s not that Hagel necessarily endorsed sending U.S. troops to fight ISIL—but, he thought, why limit one’s options?

According to this senior military officer, Hagel’s memo to Rice was “the beginning of the end for Chuck,” who couldn’t “live with the ambiguity of an ambiguous policy.” And it wasn’t just Hagel who felt that way. According to a retired senior officer who served in Iraq, Hagel’s problems with the ambiguity of White House policy “accurately reflected” the views of most senior military officers.

In the end, though, it was the NSC’s “micromanagement” of the military’s ISIL fight that most disturbed the secretary of defense and top brass. “It’s a hell of a thing,” a top military officer explained to me last week, “but the chief targeting officer for Iraq is Susan Rice. It’s very frustrating.”

That kind of micromanagement exacerbated an already tense White House-military relationship that dates back to when Adm. Michael Mullen was Joint Chiefs chairman. Mullen disagreed with Obama’s drawdown plans for Afghanistan in 2011, implying that Obama’s decision to accelerate the withdrawal was more risky than the military preferred. Obama’s rejection of the military’s advice spurred a cascade of quiet finger-pointing by military officers who supported Mullen and considered the Obama team of then-Secretary of State Hillary Clinton, U.N. Ambassador Samantha Power and Rice as “cruise missile liberals”—those dedicated to fighting wars on the cheap. Fifty years earlier, President Johnson’s top officers had leveled the same type of criticism at him.

That said, there’s little doubt that Hagel was “never a good fit as defense secretary,” his low-key reaction to a number of notable Pentagon scandals that occurred on his watch angering some of his department colleagues. “We were all waiting for him to bang the table, to get angry,” a military officer told me of Hagel’s response to the crises, which included allegations that the Pentagon had purposely misreported the increasing number of military sexual assault cases, a cheating scandal involving Air Force and Navy officers charged with overseeing the military’s nuclear program, a bribery scandal involving Navy officers who accepted cash, lavish trips and prostitutes from a Singapore-based company and a scheme in which recruiters improperly pocketed money (to the tune of some $66 million) for getting young men and women to sign up to the National Guard.