This book argues that the US Army has made four significant shifts in the content of its capstone operations doctrine along a spectrum of war since the end of WWII: 1) in 1954 it made a shift from a doctrine focused almost exclusively on mid-intensity conventional warfare to a doctrine that added significant emphasis to high-intensity nuclear warfare; 2) in 1962 it made an even greater shift in the opposite direction toward low-intensity unconventional warfare doctrine; 3) in 1976 it shifted back to an almost exclusive focus on mid-intensity conventional warfare content; 4) and this is where Army doctrine remained for 32 years until 2008, when