Bailey, a former official, writes with broad strokes across the clutch of proliferation issues, from how nuclear weapons are made to what the United States might do to restrict the spread of ballistic missiles. Hers is an accessible and affordable introduction to the subject for the newly interested, or worried. By contrast, Cordesman is a military expert, often seen on television during the Gulf War, who knows the Middle East well. His case studies are detailed, his knowledge is that of the insider, and his lessons-about arms control, for instance-are always thoughtful and sometimes challenge our intuition.