Who knew when? And why was it not believed? Laqueur (A Continent Astray. Terrorism, etc.) has scoured the evidence from June 1941, when the Germans invaded Russia and began to systematically exterminate the Jews, to the end of 1942 (by which time 2.5 million had been ""eliminated""), in order to establish just what was known in Germany, in the neutral nations, to the Allies, and among the Jews inside and outside Nazi-occupied Europe. His findings: virtually everything was known--the first massacres in Russia, the establishment of extermination camps in Poland, the deportations from other European countries, the ultimate aim--almost everywhere, through one or another conduit: in Germany, from veterans of the Eastern Front, from personnel at the camps; in the neutral nations, from fugitives or their own on-the-spot nationals; to the Allies, through the Polish underground, via Sweden and Switzerland; to the Jews directly affected, from witnesses, from letters and postcards, from the very disappearances; to world Jewry, from all these sources and the ensuing published accounts. But even in Palestine, it was not until 69 trusted Palestinians returned in November '42 that the reports were absorbed and believed. Why the near-universal incredulity? Discredited WW I propaganda about German atrocities played a part; but mostly, Laqueur avers, it was the numbing magnitude of the killings, the unimaginable horror of genocide. Plus: among the Jews affected, wishful thinking (the Germans had it in for ""Communist"" Jews, they would stop with the disdained Polish Jews, ""it couldn't happen here""); among world Jewry, a feeling of impotence and uncertainty: what should they, what could they do? Pressure on the German satellites, especially after the tide of war turned in November '42, might have saved some lives, Laqueur believes; and so might bombing the railway lines to the camps. But his chief point is not to lay blame for inaction, and definitely not to suggest willful ""suppression of information"" (the title in that sense is misleading); rather, he insists, ""democratic societies"" are inherently incapable of understanding totalitarian regimes--and their capability for extremism. Much of the evidence is new, the book as a whole is compelling and chilling.