Historian Daniel Stahl has conducted research in European and South American archives in the process of writing a new book entitled "Nazi Hunt: South America's Dictatorships and the Avenging of Nazi Crimes." The work supplies a certain and disgraceful answer to what has long been suspected: that there was a broad coalition of people -- across continents and within the courts, police, governments and administrations -- that was unwilling to act or even thwarted the prosecution of Nazi criminals for decades.