By the time Benjamin Franklin sailed for France in late 1776, he was, by a wide margin, the most famous American alive — internationally known for his scientific work on electricity years before anyone in Paris had heard of George Washington or Thomas Jefferson. That fame turned out to be one of the new nation's single most valuable diplomatic assets.

This episode follows Franklin from his origins as the fifteenth of seventeen children of a Boston candle-maker, with barely a year of formal schooling, through his rise as a printer, scientist, and civic founder in Philadelphia — and then into the specific, high-stakes diplomatic mission that may have determined whether the American Revolution was actually winnable at all. Franklin spent roughly fifteen months in France before the French government would commit to a formal alliance, navigating a foreign minister who privately wanted to help but couldn't move until he was certain the Americans could actually win. Franklin's solution, in the critical final weeks, was audacious: he let a fake story leak to the press suggesting British negotiators were already in town and might reach a deal first — applying direct pressure on France by making it look like America had other options. The threat worked. France signed.

We also examine the part of Franklin's life that complicates the celebrated diplomat: his permanent, unhealed estrangement from his own son, William, who chose the British side and whom Franklin never spoke to again.

Of all the men who signed the Declaration of Independence, only Benjamin Franklin also signed the Treaty of Paris that ended the war and the Constitution that built the government afterward — the only person whose signature appears on all three of the documents that actually built the country.

This is Day 9 of The Unfinished Founding — a File 47 daily series running through July, leading up to America's 250th anniversary of independence.

A companion article is available on Medium @ medium.com/file-47

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