On August 30, 1963, John F. Kennedy becomes the first U.S. president to have a direct phone line to the Kremlin in Moscow. The “hotline” was designed to facilitate communication between the president and Soviet premier.

The establishment of the hotline to the Kremlin came in the wake of the October 1962 Cuban Missile Crisis, in which the U.S. and U.S.S.R had come dangerously close to all-out nuclear war. Kennedy’s administration had discovered that the Soviets had planted missiles capable of launching nuclear warheads into the U.S. on the island of Cuba. The highly tense diplomatic exchange that followed was plagued by delays caused by slow and tedious communication systems. Encrypted messages had to be relayed by telegraph or radioed between the Kremlin and the Pentagon. Although Kennedy and Khrushchev were able to resolve the crisis peacefully and had both signed a nuclear test-ban treaty on August 5, 1963, fears of future “misunderstandings” led to the installation of an improved communications system.

On August 30, the White House issued a statement that the new hotline would “help reduce the risk of war occurring by accident or miscalculation.” Instead of relying on telegrammed letters that had to travel overseas, the new technology was a momentous step toward the very near future when American and Soviet leaders could simply pick up the phone and be instantly connected 24 hours a day, seven days a week. It was agreed that the line would be used only in emergencies, not for more routine governmental exchanges.

An article in The New York Times described how the new system would work: Kennedy would relay a message to the Pentagon via phone, which would be immediately typed into a teletype machine by operators at the Pentagon, encrypted and fed into a transmitter. The message could reach the Kremlin within minutes, as opposed to hours. Although a far cry from the instantaneous communication made possible by today’s cell phones and email, the technology implemented in 1963 was considered revolutionary and much more reliable and less prone to interception than a regular trans-Atlantic phone call, which had to be bounced between several countries before it reached the Kremlin.

In 1967, President Lyndon B. Johnson became the first U.S. president to use the new system during the Six Day War in the Middle East when he notified then-Soviet Premier Alexei Kosygin that he was considering sending Air Force planes into the Mediterranean.