A Republican, after the war, Brucker was assistant prosecuting attorney of
Saginaw County from 1919 to 1923, and then prosecuting attorney from 1923 to 1927. He married Clara Helen Hantel in 1923. He served as assistant attorney general of Michigan, 1927–1928, and as
Michigan Attorney General, 1928–1930. In 1930 he was elected as Michigan's 32nd governor, serving one term until being defeated in 1932 by
Democrat William Comstock. During his two years in office, the police force in Michigan increased and a new state police headquarters in
Lansing was authorized. Also Michigan enacted legislation that allowed grand juries to investigate allegations of municipal government fraud and mismanagement. In 1936, Brucker defeated incumbent
U.S. Senator James Couzens in the Republican primary elections, but lost to Democrat
Prentiss M. Brown in the general election. He was a member of the law firm of Clark, Klein, Brucker, and Waples, 1937–1954, and served as
General Counsel of the Department of Defense from 1954 to 1955, during the
Army–McCarthy hearings. In 1955, Brucker was appointed by
U.S. President Dwight D. Eisenhower as Secretary of the Army, serving from July 21, 1955, to January 19, 1961. Brucker administered the Army during a period of major technological advance, especially in the missile-satellite field, and at a time when the Army's place in the national defense structure was overshadowed by a philosophy of "
massive retaliation". Under his direction the Army instituted a five-element (pentagonal) organization concept for the division, established a
Strategic Army Corps for emergency reaction, launched the United States' first satellite,
Explorer I, and adopted the
Army Flag. ==Death==