The 'S' in Harry S. Truman’s name has caused consternation for copy editors since the moment he ascended to the presidency following the death of Franklin D. Roosevelt in 1945. If it represents a name, it should be followed by a period. Truman claimed it didn’t but insisted on signing with a period anyway.

In later years he admitted it was a nod to both his grandfathers, Anderson Shipp Truman and Solomon Young, but only after conspiracy theorists claimed it was for Sergei, an unfortunate choice of name with the Cold War looming.

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