In the U.S., it’s National Flag Day by proclamation of President Woodrow Wilson in 1916 and established by Congress in 1949 (brief history here @ Wikipedia).
Curious since President Obama signed the first proclamation of June as National Gay Pride Month if some day in this same week could be become an unofficial/official Pride Flag Day as well. It’ll give a chance to explain its origin and remember the inclusiveness that should evoke. Any thoughts? 
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