During the war in Bosnia, a United States fearful of a "body-bag backlash" refused to deploy troops, mobilising spies instead. However, when they then broke the embargo and re-armed one side, the fighting began again, resulting in 15,000 deaths and the beginning of the end for the North Atlantic Alliance. In an investigation spanning six countries, Sheena McDonald uncovers a series of incidents which have tested the Western Alliance to breaking point.