Proclamation 5121—Death of American and French Military Personnel in Beirut, Lebanon
By the President of the United States of America
As a mark of respect for the American and French military personnel who died violently in the performance of their peacekeeping duties in the tragic bombings of October 23, 1983 in Beirut, Lebanon, I hereby order, by virtue of the authority vested in me as President of the United States of America, that the flag of the United States shall be flown at half-staff upon all public buildings and grounds, at all military posts and naval stations, and on all naval vessels of the Federal Government in the District of Columbia and throughout the United States and its Territories and possessions through Monday, October 31, 1983. I also direct that the flag shall be flown at half-staff for the same length of time at all United States embassies, legations, consular offices, and other facilities abroad, including all military facilities and naval vessels and stations.
In Witness Whereof, I have hereunto set my hand this twenty-third day of October, in the year of our Lord nineteen hundred and eighty-three, and of the Independence of the United States of America the two hundred and eighth.
Ronald Reagan, Proclamation 5121—Death of American and French Military Personnel in Beirut, Lebanon Online by Gerhard Peters and John T. Woolley, The American Presidency Project https://www.presidency.ucsb.edu/node/261884