[3] During the Spanish–American War, he served as an aide to Gen. Edwin Vose Sumner, the commanding general of the cavalry division.

[2]: 11  After brief service as an instructor of physics at the United States Military Academy,[2]: 11  he served in the Philippines as governor of the island of Leyte from 1899 to 1903 and participated in the campaign against the Moros.

[1] After his promotion to brigadier general, Andrews commanded the 172nd Infantry Brigade, 86th Division at Camp Grant, Illinois.

[2]: 11 Andrews held the office Assistant Secretary of the Treasury, beginning in March 1925,[5] after Roy Asa Haynes.

He reorganized the bureau in 1925, resulting in the layoffs of numerous agents, including Izzy Einstein and Moe Smith in New York, who were nationally the most successful and famous team.