In The Echo of Battle, Prof. Linn, of Texas A&M, who has written widely in American military history, takes a look at the principal "types" of American army officers and how they have shaped the army since its formation. 

Linn classifies American officers in three broad categories.  The "Guardians," view war as "an engineering problem," requiring the proper application of art and science to resolve, and have generally been conservative in foreign affairs, such as Colin Powell.  The "Heroes," such as George S. Patton, were adaptable and flexible, holding that "wars are fought by men."  The "Managers," such as George C. Marshall or Dwight D. Eisenhower, viewed war as a matter of proper mobilization and organization of resources. 

In Linn's view, the tensions and interactions among these three types of officers have been critical in shaping America ?s military policy and strategy since the professionalization of the army in the 1820s, and continues in the present, as demonstrated by the controversies in senior military leadership over the planning for Operating Iraqi Freedom.

Although one can certainly raise objections to Linn's thesis, and can also wonder where, for example, Winfield Scott, George B. McClellan, and John J. Pershing fit in, The Echo of Battle is an important work for anyone interested in the American way or war.