The proof is not that ancient. Pi was proven to be irrational in 1761, and proven to be transcendental in 1882.

For a long time the problem was known as “squaring the circle”: Given a circle in a plane, construct a square with the same area using a compass and straightedge. This was a famous unsolved problem in mathematics from antiquity all the way through the renaissance.

Or even just 9 months ago, when he told the leader of Germany that D-Day “was not a pleasant day for you.”

Japan actually tried to coordinate a formal declaration of war to be submitted immediately before the attack commenced. But due to technical and logistical problems, the communique was not read by American diplomats until after the attack.