"Lincoln's Code: The Laws of War in American History," by John Fabian Witt

Published by Free Press (2012)

Reviewed by Amy J. Sennett

In the weeks following the September 2012 publication of Yale Law School Professor John Fabian Witt’s Lincoln’s Code, reviewers praised the book for providing rich, yet readable historical context to the debate over the role of the laws of war in American foreign policy. Witt’s detailed narrative offers a middle ground between the idea that the Bush Administration’s war on terror was a radical break with American adherence to the laws of war and the belief that the laws of war are a pragmatic set of rules with which the U.S. complies only when in its interest.

Witt also acknowledges that the laws of war have been politicized since the Founding. The first Americans were quick to embrace the laws of war in their effort to establish the membership of the United States in the club of civilized nations. Witt notes that conveniently, “the confluence of principle and interest in the American Revolution” made it easier for General Washington and other leaders to adhere to the laws of war. The human treatment of civilians, Washington reminded his officers, would secure the affections of the people. Given its relative lack of military might compared to its European adversaries, the young republic pioneered an Enlightenment vision for warfare in its own self-interest – one that set put sharp restraints on the conduct of warring nations.

But there was another element of self-interest embedded in that restraint. The Enlightenment’s humanitarian limits on the laws of war fiercely protected private property. Witt writes: “And therein lay the humanitarian paradox of the early American laws of warfare. … [F]or many Americans, the preservation of private property in slaves counted as one of the law’s chief humanitarian accomplishments.”

With this point, Witt transitions to the more complex themes at the heart of his book. Witt is less interested in settling the score between liberals and realists and more interested in how ideals -- particularly the justice of one’s cause -- have influenced the laws of war. Witt explores the issue through the transitional document of Lincoln’s code -- the 1863 code of wartime conduct authorized by President Lincoln and drafted by legal academic Francis Lieber -- that pioneered a shift from the prevailing Enlightenment rules of civilized, limited warfare to a view that refused to separate the rules for combat from the justice of the cause.

For Lieber, Enlightenment jurists erred by regulating conduct in armed conflict without reference to the legitimacy of the war aims of either side. Ends, in Lieber’s view, could not be separated from means; to the contrary, they helped determine the scope and character of the conduct appropriate to the situation. According to Witt, the only question of Leiber’s laws of war was a simple one: Was the destruction “greater than necessary?”

Witt describes Lieber’s views as “a compelling but potentially ferocious framework for the laws of war.” Outside of torture, virtually all destruction seemed permissible so long as it was necessary to advance a legitimate war effort. Lieber modified Clausewitz’s definition of war, describing war as a fight against an enemy “to compel him to peace at my will.” For Lieber and Lincoln, in the American Civil War, that peace was one without slavery.

Lincoln’s thinking on slavery and the laws of war took longer to evolve. In August 1861, when one of his generals attempted to emancipate the slaves under martial law, Lincoln countermanded the order. According to Witt, “Civilized warfare, the United States had insisted, prohibited acts that might incite slaves into a war of servile insurrection and indiscriminate violence.” But in less than a year, Lincoln would change his mind. By early summer 1862, the Union war effort had stalled, and Lincoln saw “an unmistakable connection between limited Enlightenment-style war and the failure of Union forces to bring the war nearer to a close.” Within the week, Lincoln had resolved on emancipation.

According to Witt, Lincoln believed the legal limits on war reflected the fact that human beings could never know for sure that they comprehended God’s justice. But why go to war at all -- why set in motion war’s terrible violence -- if one was not sure one was right? The moral leader had to act and had to use reason to come to a conclusion as to what justice required.

For Lincoln, Witt writes, “Emancipation pressed humanitarian limits and justice back together by measuring the limits on the conduct by reference to the justice of its ends.” In September 1962, when critics derided the Emancipation Proclamation as “nothing more than military necessity,” they missed the fact that mere military necessity was momentous. Witt writes: “Even the flat affect of the Proclamation itself was exquisitely attuned to moral restraint in warfare … Lincoln knew precisely the risks posed by bringing justice back into the conduct of war. Lincoln announced the Emancipation with the modesty of a man who knew that he could never understand for certain how God willed him to act, but who knew that he had to act nonetheless.”

As January 1, 1863, the effective date for Emancipation drew near, the treatment of black soldiers was a live question. Jefferson Davis issued proclamations condemning emancipation and ordering that armed “negro slaves” be treated as criminals. Other Confederate officers planned to give black soldiers no opportunity to surrender. In response, Leiber’s code declared that “[t]he law of nations knows no distinction of color” and stated that “[n]o belligerent has a right to declare that enemies of a certain class, color, or condition, when properly organized as soldiers, will not be treated by him as public enemies.” His code “integrated the concept of justice into a body of law that had been designed to set justice aside for the sake of humanity.”

Asserting the priority of justice over humanitarianism had almost immediate practical consequences. Sherman’s 1864 assault on Atlanta and March to the Sea that followed were “the practical embodiment of the code’s unsettling critique of the orthodox laws of war.” A year earlier, in the summer or 1863, Lincoln decided the Union would not participate in prisoner exchanges so long as the South continued executions of black soldiers. As a result, an estimated 55,000 men died in Civil War prison camps. Witt writes, “If the law of war’s only goal were reducing human suffering, this would have been a searing indictment of its legacy. But the Union’s code embodied a mix of purposes. Lessening humanitarian suffering was one. But so was justice for black soldiers and victory for the Union.”

Yet Witt describes Lincoln and Lieber as “on a knife’s edge between humility and justice.” By his Second Inaugural Address in March 1865, Lincoln was already laying the groundwork for a more humble approach to the Confederate leaders in the postwar world. While it might have seemed impossible that those who fought to defend slavery could lay claim to God’s authority, Witt writes, Lincoln cautioned against overconfidence. “Let us judge not that we be not judged,” Lincoln said. Witt quotes Lincoln as urging this audience to leave revenge behind and move forward to “bind up the nation’s wounds.” John Wilkes Booth, Witt notes, eliminated the Union leader most committed to the amnesty tradition in postwar justice.

Witt’s book unwinds quickly as he shifts from the Civil War to the19^th century wars of colonization. He writes: “Would the conduct that had once seemed morally permissible for the world-historic ends of abolition also prove justified in wars of empire? … [A]t the turn of the twentieth century, wars of empire sundered the connection between the new laws of war and the moral force of the anti-slavery effort that had precipitated their birth. Therein loomed a crisis for the law.”

But Witt does not provide much explanation for the resolution of this crisis. In the third section of the book, he details several massacres of Native Americans in the western United States and incidents of torture in the Philippine-American War. But this does not fully explain why, in 1914, when international lawyers and American statesmen updated Lieber’s Code, they returned to an Enlightenment approach to the laws of war. Witt claims that they remained true to Lincoln and Lieber’s intentions, but he glosses over the fact that many harsh tactics permitted under their code were banned in the updated code. With only minor adjustments, these new rules were carried onto the battlefields of World War I and II and into the courtrooms of Nuremberg, informing the twentieth and twenty-first century conception of the laws of war.

Given Lincoln and Lieber’s conviction that the justice, before humanitarian concerns, ought to inform the laws of war, Witt’s book should give readers today pause. Modern international humanitarian law (the name gives itself away) emphasizes limited war principles like necessity and proportionality. Some may say the world today has more gray zones than the fight to end slavery, but certainly tens of thousands of Southerners would not have given their lives for a cause they did not find just. Leiber believed “short wars were more humane wars, and the way to ensure short wars was to fight them as fiercely as possible. The prospect of fierce wars might even prevent war from breaking out in the first place.” With technology like drones that reduce the human costs of war for at least one side, does the significance of the justice of the cause become less of a factor in the calculation to go to war? If justice not a major part of the calculus, are certain causes less likely to spur military intervention even when the justice of the cause seems clear? Initial reviews suggested that Witt’s narrative contained lessons about American adherence to the laws of war in war that would inform the debate over Guantanamo, torture and targeted killings. But Lincoln and Lieber’s thinking about justice might be more applicable to issues in the headlines this summer—Syria comes to mind—and calculations weighing the cause and the cost of war.

(Amy Sennett is a litigation associate at Arnold & Porter LLP in Washington, D.C. and will be judicial clerk on the District Court for the Eastern District of Pennsylvania beginning in September.)