1963: US-USSR agreed to "hotline."
John F. Kennedy became the first U.S. president to have a direct line to the Kremlin in Moscow. The “hotline” was designed to facilitate communication between the president and Soviet premier. However, though the public perception of a "Red Phone" that went directly to Moscow is not exactly how the process worked. The "hotline" would first involve a call to the Pentagon where the message would be typed into a teletype machine, encoded, and then transmitted. The message would reach Moscow within minutes. Read the excerpt below to learn more.
Excerpted from History.gov:
"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."