It was 1962. The United States of America were wary of the Soviet actions in Cuba. The Cuban Missile Crisis was a tense time.
Point of Divergence
The communication man was annoyed with his employer after an unexpected pay cut. Following this, he decided to scramble and change all messages into random numbers.
One of these messages, was John.F Kennedy's message. By a stroke of luck, it happened to consist only of zero's and one's.
When the Soviet's received it, their technological experts were shocked. These zero's and one's appeared to them as Binary Code, and that message in Binary was "we wll kil u. we have nukes detonating at 49:34". Taking note of the terrible grammar, they eventually decided to retaliate before their forces diminished.
What happened next was like a firework show, but deadlier. America and the Soviets were devasted quickly, having both fired weapons at each other. Radiation lingered in the areas, and were unrecognisable.
The surviving nations now have to cope with the loss of two great powers.