Witness for the Prosecution

In the six decades following world War II, no fewer than 313 international and internal conflicts have erupted, killing up to 101 million people by one estimate. Many were victims of crimes against humanity, but most of the perpetrators have managed to get off scot-free. In the postwar period, according to a recent study published by legal scholar M. Cherif Bassiouni, just 823 people were indicted for violations of international humanitarian law, even though the ratio of civilian to military fatalities was staggeringly high — perhaps 9,000 to 1.

In his new memoir All the Missing Souls, David Scheffer recounts the effort to extend the reach of international justice to war zones and collapsing societies. As America's ambassador-at-large for war-crimes issues from 1997 to 2001 (and the first person to hold the job), Scheffer opens up diaries and dispatches from within the halls of power, linking failures to prevent mass murder and genocide — in Rwanda, the Balkans, Sierra Leone and elsewhere — together with politicized attempts to build justice after (and sometimes during) the fact. (See photos of "Ratko Mladic: The Long Shadow of the Bosnian War.")

He has also composed what is doubtless the most heartfelt apology that any of the Clinton Administration's former members (the 42nd U.S. President included) have offered to the people of Rwanda — as many as a million of whom were murdered while the world looked the other way in 1994. "For those of us in the policy rooms at the time, the memory of our vacillation over the horror is sickening and will never be extinguished," he writes, before laying out in awful detail (and with the help of declassified State Department cables) how U.S. officials simply did not acknowledge the reality of genocide until it was too late. "I owe the victims and their families my soul every day."

Secretary of State Madeleine Albright created Scheffer's ambassadorship in the second Clinton term, but Scheffer reveals how deeply their relations suffered as he began to ruffle diplomats' feathers. After Scheffer confronted, for the umpteenth time, the French government for refusing to arrest Bosnian-Serb President Radovan Karadzic, Albright — perhaps to appease France — used an intermediary to tell Scheffer to desist.

The central contradiction that emerges is that both Scheffer's greatest successes and worst failures were due to a single fact: he was employed by the U.S. It meant that he had clout — but on behalf of a country that has long viewed international law as something that only binds other nations. For example, at the behest of the unbending top brass at the Pentagon, Scheffer was forced during the 1998 negotiations for the creation of the International Criminal Court to seek impunity for all U.S. service personnel, a proposal he describes as "institutional suicide" and one that was roundly defeated. "I appeared as the guardian of impunity, rather than its slayer," he writes. (See the top 15 toppled dictators.)

Scheffer was later outraged to see his work dismantled by the Bush Administration, which not only rejected and undermined the International Criminal Court (and described the Geneva Conventions of 1949 as "quaint"), but also pitched headlong into torture, black sites, extraordinary rendition and war. "The entire legal framework of the so-called 'war on terror' was premised on ignoring or rejecting the jurisprudence of the war crimes tribunals and the evolution of atrocity law during the 1990s," Scheffer writes.

This impeccably documented work stands as a condemnation not just of such Bush-era expediency but also of moral compromise at the expense of the powerless. It's also the story of an attempt to attain the most strenuous of goals: upholding civilization in the face of monstrous evil. Scheffer is one of the very few people who can tell it.

Watch TIME"s video "Objects Identify Long-Dead Victims of Bosnian War."

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