Happened before, in 1932
Bonus Army - Wikipedia, the free encyclopedia
The Army intervention was led by WWII hero Douglas MacArthur, assisted by Dwight Eisenhower, and with 6 tanks commanded by George Patton vs. veterans/women/kids. (strange, but all true).
...And again in the Longshore riots of San Francisco in 1934
1934 West Coast waterfront strike - Wikipedia, the free encyclopedia
This time the Calif. National Guard, with armored cars and tripod mounted machine guns.(not used thankfully)
Link to page with pics of tanks on the streets of San Francisco! Just a Car Guy: 1934, the all the west coast longshoremen, teamsters, and seamen unions went on strike and the national guard was called in
History often repeats itself.