The query combines two distinct American observances. The date specified, September 11, refers to Patriot Day, a national day of remembrance. This is often confused with Patriots' Day, a regional public holiday observed on the third Monday of April in Massachusetts and Maine.
Patriot Day, held annually on September 11, was established to honor the individuals who lost their lives in the terrorist attacks of September 11, 2001. Formally designated as the "National Day of Service and Remembrance," it is a day for solemn commemoration. By law, the President directs that the flag of the United States be flown at half-staff at all federal buildings and establishments, and a moment of silence is observed to correspond with the times of the attacks. In contrast, Patriots' Day, celebrated in April, commemorates the anniversary of the Battles of Lexington and Concord in 1775, which were the first armed conflicts of the American Revolutionary War. It is a state holiday associated with historical reenactments and civic events, most notably the Boston Marathon.
The primary source of confusion is the similarity in the names of the two events. The key distinction lies in their meaning, date, and designation. Patriot Day on September 11 is a nationwide day of solemn remembrance for a 21st-century tragedy. Patriots' Day in April is a state-level holiday celebrating a foundational event in American history from the 18th century.
