Display the colors.
The idea for a celebration of the birthday for the flag was started in 1885 and went through several years and organizations supporting the idea. President Wilson did a proclamation in 1916 but it was not until August 3, 1949, that President Truman signed an Act of Congress designating the date National Flag Day.
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"Resolved, that the flag of the United States be thirteen stripes, alternate red and white; that the union be thirteen stars, white in a blue field representing a new constellation."