Crusade in Europe, which is a pretty amazing book.
These days it's hard to believe how poor (in nearly every sense except leadership) our military was in the late 1930's and how rapidly it grew. The planning and logistics - an incredible effort. This is a great book for those people who know virtually nothing about what it takes to put major forces, fully equipped and trained, into the field.
General Eisenhower was a straight shooter who greatly admired General George Marshall and his leadership - this excerpt is from when the future President was chief of OPD on Marshall's staff: