http://en.wikipedia.org/wiki/Bonus_Army Makes sense not to bring back all those Solders who could end up unemployed. "On July 28, U.S. Attorney General Mitchell ordered the veterans removed from all government property. Washington police met with resistance, shots were fired and two veterans were killed. President Hoover then ordered the army to clear out the veterans. The infantry and cavalry were supported by six tanks, and commanded by Army Chief of Staff General Douglas MacArthur. Major, later President, Dwight D. Eisenhower was his liaison with Washington police, and Major George Patton led the cavalry. The Bonus Army, their wives and children were driven out with fixed bayonets and adamsite gas, an arsenical vomiting agent, and their shelters and belongings burned. Two more of the veterans, and an unknown number of babies and children, died (accounts range from one to "a number" of casualties).