Can generals openly defy presidents?
Not if the general wants to keep his job. American history is replete with examples of presidents dismissing military leaders whose loyalty or obedience came into question. During the Civil War, Abraham Lincoln sacked George McClellan after the Union Army commander continually refused Lincoln’s entreaties that he attack Confederate forces. When Lt. Gen. Nelson A. Miles disagreed with William McKinley over how to wage the Spanish-American War, Miles was packed off to a minor skirmish in Puerto Rico. In 1965, Lyndon Johnson forced out Air Force Gen. Curtis LeMay because he criticized the White House for not carpet-bombing North Vietnamese cities. The best-known general-president showdown was probably between Harry Truman and Gen. Douglas Mac­Arthur over the Korean War.

What was the core of their disagreement?
Truman was determined to confine hostilities to the Korean peninsula, fearing that if he broadened the conflict, the Soviet Union might enter the fray, raising the specter of nuclear war. MacArthur, however, wanted to deal with the communist menace directly by attacking China, which had poured troops into Korea. He publicly assailed the White House for being too timid—in effect, challenging Truman’s backbone and patriotism. Declaring that “there is no substitute for victory,” MacArthur said that Truman’s refusal to expand the war into China imposed “an enormous handicap, without precedent in military history.” When the general then threatened Beijing with “imminent military collapse,” Truman was furious. On April 11, 1951, he fired MacArthur.

What was the reaction?
At the time, most Americans thought that MacArthur, the most celebrated general of World War II, had been shabbily treated. But Truman later said, “I fired him because he wouldn’t respect the authority of the president. I didn’t fire him because he was a dumb
son of a bitch—although he was, but that’s not against the law for
generals.” Today, the consensus among historians is that Truman was justified in canning MacArthur for insubordination.

Can’t generals have views?
Of course they can. Truman himself said, “Full and vigorous debate on matters of national policy is a vital element in the constitutional system of our free democracy.” But in our democratic system, the president is the boss. Generals are expected to give presidents their best advice, and can advocate strongly for their points of view, but then salute when the president makes a policy decision. If generals have remaining reservations, they are expected to keep them to themselves.

Where does this tradition come from?
It’s firmly grounded in the U.S. Constitution, which explicitly established civilian control over the military by naming the president commander in chief. Congress, meanwhile, was given the power to raise, support, and maintain an army and a navy and “to declare war”—meaning that the military would be subservient to not one but two elected branches. Indeed, the Founding Fathers were quite concerned about the threat of an unfettered military. “The greatest danger to liberty is from large standing armies,” James Madison said during the 1787 constitutional convention.

How does ‘civilian control’ work?
As a general matter, presidents set broad military goals but let the generals decide how to best achieve them. Some presidents, though, are more engaged than others. Lincoln took such a hands-on role in directing the Civil War that he often acted like a general himself. Franklin Roosevelt involved himself day-to-day with World War II military strategy, overruling his generals when they bitterly opposed the invasion of North Africa in 1942. Not surprisingly, the military tends to resent presidential intervention. Lyndon B. Johnson demoralized and frustrated his Air Force generals by handpicking bomb targets in Vietnam.

Should presidents defer to military expertise?
Some of the time, certainly. Civilians don’t have a monopoly on wisdom, as John F. Kennedy and LBJ found when they listened to such civilian advisors as Secretary of Defense Robert McNamara. The result, says historian Jean Edward Smith, was “the eminently logical but tactically catastrophic escalation in Vietnam.” In early 2003, during the lead-up to the Iraq war, the Bush White House brushed aside Army Chief of Staff Gen. Eric Shinseki’s testimony that it would take “several hundred thousand” soldiers to pacify Iraq; a few months after his unwelcome assessment—which turned out to be accurate—he was gone.

So what’s the right balance?
There’s no simple answer. Ever since the Vietnam War, generals have felt pressure to speak out when they believe they’re being told to do the impossible. The public may benefit from this higher moral standard, even if open dissent conflicts with the military’s traditional subordination to the elected branches. But it’s a given that in a real standoff with the president, any general, no matter how brilliant, will lose. “Officers owe their loyalty to the president,” said Dwight D. Eisenhower’s son, John, a retired brigadier general and military historian, “and have an obligation to resign if they are unable to carry out the commander in chief’s policies.”

McChrystal’s challenge
In late August, Gen. Stanley McChrystal, commander of U.S. forces in Afghanistan, privately warned the White House in an internal report that unless the U.S. committed up to 45,000 additional troops, defeating the insurgency would be “no longer possible.” The advice became anything but private, though, after The Washington Post obtained a copy of the report a month later, creating intense pressure on President Obama to “listen to his generals.” McChrystal upped the ante a week later when he expanded on his view in a speech. When asked whether he supported a more limited strategy to target militants—as Vice President Joe Biden has advocated—he said, “the short answer is no.” President Obama promptly summoned Mc­Chrystal for what was by all accounts an awkward 25-minute meeting. There have been no indications that McChrystal’s job is in danger, though he has been noticeably quiet lately. “It is imperative,” said Defense Secretary Robert Gates, “that all of us taking part in these deliberations, civilians and military alike, provide our best advice to the president—candidly but privately.”