Ask yourself why you were never taught this in school.
Although there were planes used against the miners in the Battle of Blair Mountain, it is not true that this was the first time planes were used to drop bombs on American soil against Americans.
The Battle of Blair Mountain took place in August and September of 1921. Just a few months prior to that, on May 31 and June 1, planes were also used to help destroy the Greenwood district of Tulsa, Oklahoma, a prosperous black neighborhood nicknamed The Black Wall Street. At least 39 people died during the event, which is known as the Tulsa Race Massacre. Hundreds were wounded, and 6,000 black people lost their homes.
Both of these events were hugely important moments in American history.
Ask yourself why neither was taught to you in school. Also ask your local school board.