On this day, October 14, in 1890, Dwight Eisenhower was born. There are many interesting tidbits about Ike — like his problem with gambling, or his fascination with Gettysburg, or the fact that someone almost brained him with an unopened block of confetti during a campaign parade in 1952 — but one of the most astonishing things is how close he came to leading a very different life than the one we know.

When Ike was a teenager, he scraped his knee. An infection set in, and in those days before antibiotics, it spread without check. The blood poisoning — as they called it in those days — moved toward his groin, and his doctor said the leg should come off before the infection turned fatal. Ike refused. He kept the leg, and his body eventually fought off the infection, leaving him whole and healthy.

Had that amputation taken place, Eisenhower would never have been admitted to West Point. Had he never gone to West Point, he would never have become the Supreme Commander of the Allied Expeditionary Force in WWII. Had someone else commanded the Allies in that war, who knows how it would have played out?

Perhaps the fate of the world hinged on a scraped knee.