October 1962. Thirteen days when the United States and the Soviet Union came within one misread signal of the end of everything. Afterwards, both sides admitted the truth: they had almost burned the world because they could not simply ask each other what they meant.
So they built a line. Not a red phone, a teletype, direct between Washington and Moscow, encrypted, always on. Its whole purpose: no crisis would ever again depend on guessing at the other side's silence.
It went live on August 30, 1963. The first words to cross it were a test sentence, built to use every letter of the alphabet: THE QUICK BROWN FOX JUMPED OVER THE LAZY DOG'S BACK 1234567890. All caps, because the machine had no lowercase.
Moscow answered with a test of its own, every letter of the Cyrillic alphabet in one sentence. The line worked.
For years the testing continued with Shakespeare, Mark Twain, a first-aid manual. One day a Soviet diplomat asked what the fox sentence really meant. Nothing, he was told. It only means all the keys work.
The line is still in service today. Same idea, all these years: when you are not sure what the other side means, ask. Do not let silence become an answer.