When the superpowers drew close to the edge of the nuclear abyss during both the Cuban Missile Crisis and the Able Archer/VRYAN Crisis , they learned and grew from their mistakes and miscalculations that led them to be within view of mutual assured destruction . Andropov was followed as Soviet leader by Konstantin Chernenko , who in turn was followed by Mikhail Gorbachev , and Gorbachev brought a far less hostile , ideological , and reflexively skeptical approach to the relations between the superpowers , helping to build an atmosphere of trust between the two . Reagan had a figurative conversion on the road to Damascus regarding nuclear weapons and ICBMs following this crisis , discarding his preconceived notions of general Soviet bad faith , leading him to come full circle and famously declare that " Nuclear war can not be won and must not be fought " . These new attitudes on both sides nearly brought about the disarmament and destruction of ICBMs , long-range SLBMs , and , possibly even nuclear weapons themselves at a groundbreaking disarmament summit between Gorbachev and Reagan at Reykjavík in 1986 . ( The sticking point causing agreement to be unreachable was the SDI Program , just as missile defense continues to be a thorn in the side of the Russians today . ) However , progress was made ; the INF Treaty , the Conventional Forces in Europe Treaty , and the START Treaty could be said to be the result of the change in leaders and leaders ' attitudes that the Able Archer/VRYAN crisis facilitated , just as the Non-Proliferation Treaty and the Partial Test Ban Treaty , as well as U.S.-Soviet détente , were the result of the Cuban Missile Crisis
summit
Reykjavík Summit
Pre-emptive nuclear strike