Since I am intensely interested in the subject of the American involvement in the intervention of North Russia just after the First World War (where the U.S. 339th Infantry fought against the 6th Red Army), I have a good many books on the subject, from "Fighting the Bolsheviki" to the more recent "Stillborn Crusade," and I have notes I made while researching original documents at the U.S. Library of Congress. But when I want to think in broader terms, I always pull out my copy of "The Decision to Intervene." It allows me to review the general situation at the time, including the activities of the Red Cross (who put the "Red" in the "Red Cross" Ha! Ha!), the U.S. troops in Siberia, and the Czechslovak situation at the time. I would be lost without this book. I highly recommend it!