Since its official birth on 14 June 1775-over a year before the Declaration of Independence-the United States Army has played a vital role in the growth and development of the American nation. Drawing on both long-standing militia traditions and recently introduced professional standards, it won the new Republic's independence in an arduous eight-year struggle against Great Britain. At times it provided the lone symbol of nationhood around which patriots could rally. During the Civil War it preserved the Union through four years of bitter conflict that turned brother against brother. It has...