In September 1796, George Washington sat down and wrote a letter he never mailed. It ran in newspapers instead — the American Daily Advertiser printed it first, under the title “The Address of General Washington To The People of The United States.” Nowhere in it does Washington cite a law, a court ruling, or a clause of the Constitution telling him he had to step down after two terms. There wasn’t one. Article II says nothing about how many terms a President can serve. Washington simply decided, on his own, that two was enough, and walked away from the most powerful office in a country that had just fought a war to avoid having a king at all.

The decision mattered more than the specific words. Washington could almost certainly have won a third term easily — he was, by a wide margin, the most trusted man in the country. That he chose not to run told the country something no clause in the Constitution had: that the presidency was a temporary job people were expected to leave, not a throne they were expected to keep. For the next century and a half, every President who reached the end of a second term stepped aside, not because any statute required it, but because Washington had, and nobody wanted to be the one who broke the pattern.

Franklin Roosevelt broke it. In 1940, with the country climbing out of the Depression and watching a second world war spread across Europe, Roosevelt accepted the Democratic nomination for a third term. He wasn’t violating any written rule — there genuinely wasn’t one to violate. He was breaking a norm that had stood since 1796, unwritten but unbroken, treated by nearly everyone as though it carried the weight of law even though it never actually had any. Roosevelt won that election, and then won a fourth term in 1944, before dying in office in April 1945, a few months into his final term.

Congress moved quickly once the precedent had visibly failed to hold on its own. In 1947, less than two years after Roosevelt’s death, Congress passed the 22nd Amendment, formally limiting Presidents to two elected terms. It took until 1951 to secure ratification from three-quarters of the states, but once it did, the norm Washington had set by choice became a rule no President could break by choice, ever again.

The gap between those two moments — 1796 and 1951 — is the real story here, and it’s a pattern that shows up more than once in how the presidency has actually developed. The Constitution’s Article II is short by design, and short documents leave room. Sometimes that room gets filled by a President’s personal restraint, treated as though it were binding even though it technically isn’t. Sometimes, eventually, someone tests whether the restraint was ever really a rule at all — and when it turns out it wasn’t, the only way to make it permanent is to write it down properly, the way the 22nd Amendment finally did. Washington’s choice held for 144 years on nothing but reputation and expectation. It took one president willing to break it, and a constitutional amendment, to turn it into something no future president could ever choose to ignore.