For too long now, command accountability for our troops’ misconduct in wartime has been more theoretical than real. The latest scandal to erupt in Afghanistan — photographs of American soldiers amusing themselves with dismembered Taliban corpses — suggests that it’s past time to confront this problem.

On the question of accountability, the military’s ethic is clear: With authority comes responsibility. More specifically, commanders bear responsibility for everything that happens within their jurisdiction. This decree supposedly applies to high-ranking generals as much as lowly lieutenants.

Once upon a time, the standard for implementing this code was straightforward: Win, and you gain fame and fortune; fail to win, and you’re toast. As commander in chief during the Civil War, Abraham Lincoln enforced this standard ruthlessly. As a result, Ulysses S. Grant and William T. Sherman achieved a measure of immortality. Meanwhile, Irvin McDowell, George McClellan, John Pope, Ambrose Burnside, Joseph Hooker and George Meade, among a host of other mediocrities, found themselves unemployed or consigned to lesser positions.

In the post-9/11 era, President George W. Bush abandoned this standard. In 2003, Gen. Tommy Franks presided over a campaign in Iraq that dispersed a pathetic local army even as Franks neglected to consider what might ensue. The answer was not long in coming: chaos and a far uglier and more costly conflict than Americans had bargained for.

Historians will probably place Franks in the company of Burnside and Hooker rather than Grant and Sherman. Yet, for whatever reason, Bush glossed over his field commander’s shortcomings, ordained him a great leader and awarded him the Medal of Freedom. Franks had neither won nor lost his war; he had merely mismanaged it and then moved on, washing his hands of the mess. Here was a troubling precedent.

War induces barbarism, and the Iraq war proved no exception. Soon enough, egregious transgressions by U.S. troops surfaced. Abu Ghraib provides one especially notorious example; the massacre at Haditha another. But there were others, now mostly forgotten, at least by Americans — among them the Iraq insurgency’s equivalent of the Boston Massacre. In Fallujah on April 28, 2003, with Franks still in command, U.S. troops opened fire on Iraqi demonstrators, killing more than a dozen and wounding several dozen more.

The Pentagon declared each of these an aberration. In each instance, extensive investigation singled out a handful of minions for punishment. In each, senior commanders escaped unscathed. (Abu Ghraib is the partial exception that proves the rule: In the scandal’s aftermath, a female Army Reserve brigadier general — not quite a member of the club — lost her star, a fate thus far shared with no male counterpart and no regular officer.)

In an earlier day, this misconduct might not have mattered. When Sherman’s troops marched to the sea in 1864, few cared about any atrocities they might commit. The object of the exercise, after all, was not to win Confederate hearts and minds but, as Sherman succinctly put it, to “make Georgia howl.” Similarly, although the desecration of remains by U.S. troops today pales in comparison with the treatment visited upon Japanese dead during World War II, ensuring that Marines at Peleliu or Okinawa complied with the Hague Conventions did not figure as a priority. Their job was to kill.

Yet, like it or not, our wars differ from those wars. The attenuated definition of command responsibility that prevailed after Sept. 11, 2001, not only let senior commanders off the hook; in wars where killing is not enough, it also compromised overall military effectiveness.

Much to his credit, when Robert Gates became secretary of defense in 2006, he sought to reverse this erosion of senior officer accountability. When the Air Force demonstrated a cavalier attitude toward managing its nuclear inventory, Gates fired the service’s chief of staff. When The Washington Post broke a story about wounded warriors warehoused in substandard conditions at Walter Reed, Gates handed both the two-star hospital commander and the three-star Army surgeon general their walking papers.

When Gen. Stanley McChrystal, chosen by President Obama to run the Afghanistan war, sat idly by as members of his staff expressed their contempt for administration officials, he too lost his job. McChrystal himself hadn’t said anything all that objectionable. His offense lay in failing to school his loud-mouthed subordinates in the principle of civilian control of the military.

Yet when it comes to misdeeds on or near the battlefield — troops urinating on Taliban corpses, burning Korans, allegedly wandering away from base to murder civilians in cold blood — the pre-Gates norms stubbornly persist. If fault is found, it invariably fixes responsibility and imposes penalties at echelons well below those occupied by the people said to be in charge. The fall guy ends up being the little guy.

Granted, each of these incidents occurs in a context. Protracted conflicts undermine discipline, and those of the past decade have been the longest in U.S. history. Soldiers sent to wage frustrating and almost certainly unwinnable wars to which the public has become indifferent deserve considerable sympathy. The fact that those troops are of a generation seemingly compelled to record and “share” their personal experiences — whether quotidian or silly or depraved — offers a further complication. (Marines prying gold teeth out of dead Japanese soldiers did not enshrine their acts on iPhones and send the results to a network of best buddies.)

Furthermore, we should not overstate the reach of command authority. Only someone innocent of actual military experience will imagine that a directive from an American four-star general elicits enthusiastic and universal assent. Orders are often misconstrued, reinterpreted, overlooked or selectively disobeyed — hence, the need to restate them while demanding full compliance.

Yet anyone who cherishes the military professional ethic will see those explanations — whatever their value in providing context — for what they are: excuses for a repeated failure to enforce standards. That failure, which undermines any prospect for mission success, however loosely defined, is ultimately a failure of leadership.

This latest scandal, surfacing on Gen. John Allen’s watch, actually occurred in February 2010, when Gen. David Petraeus, then head of U.S. Central Command, had overall responsibility for the war’s direction. The revelation dents the image of mastery that Petraeus and his acolytes carefully cultivated. Yet the interval between the act and its becoming public knowledge suggests that this is unlikely to be the last such incident we will have to endure.

The best way to stanch this outpouring of embarrassing news from Afghanistan is to bring our soldiers home, an option that many Americans find increasingly attractive. In the interim, however, we should reassert a standard of command responsibility that Lincoln would have understood. Yes, when soldiers behave badly, the harsh hand of discipline should fall on individual perpetrators. Yet soldier misconduct expresses professional malpractice at all levels. This epidemic will subside only once we recognize that.

Gates understood the basic proposition. Leaders shape institutions. But no leader is irreplaceable — sometimes nothing beats replacing a few near the top to focus the attention of the rest. For an American military well into a second exhausting decade of continuous war, this is one of those times.

Andrew J. Bacevich, who teaches at Boston University, is the editor of “The Short American Century: A Postmortem.”

Read more from Outlook:

Withdrawal from Iraq marks the end of U.S. supremacy

In endless war, four-star arrogance

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