On October 16–28, the world is marking the 50th anniversary of the Cuban Missile Crisis, a standoff between the United States and the former Soviet Union that nearly ended in a nuclear war between the two superpowers.

The confrontation of the Cold War still affects the relationship between the U.S. and Russia to this day and is a cautionary tale in a world where nuclear proliferation is rampant.

In 1962, the Cold War rivals used their arsenal of weapons of mass destruction as a means of nuclear deterrence and a symbol of their awesome military power. Imbued with communist ideology and encouraged by decolonization, the Soviet Union was supporting the revolutionary Castro regime, for the first time projecting power into the Western Hemisphere.

Castro, seeking a nuclear umbrella, had encouraged the Kremlin to bring its nukes to Cuba and point them at the U.S. Both parties were rapidly building up their stockpiles, vehemently believing that mutual assured destruction (MAD) is the only way to deter the other party from using their nuclear weapons.

After the two countries found themselves on the brink in October 1962, the negotiations between Presidents John F. Kennedy and Soviet Premier Nikita Khrushchev were the only thing that prevented a full-out war. It was the secret diplomacy of the leaders that helped avoid the potential crisis. Importantly, communists did not believe in martyrdom and afterlife, which fundamentally distinguishes them from today’s Iranian leadership.

The bold move by Khrushchev to place nuclear weapons in Cuba was an indication of his disdain toward Kennedy: After taking measure of the youthful American President, he viewed him as inexperienced and a weaker leader than former President Dwight D. Eisenhower. This overconfidence prompted Khrushchev to place the nuclear weapons in Cuba.

The crisis was resolved with the secret agreement of the Soviet Union to withdraw its weapons from Cuba and the U.S. promise not to invade Cuba. Kennedy also committed to withdraw U.S. nukes from Italy and Turkey. Additionally, an emergency phone link between the Kremlin and the White House was installed to prevent the next Armageddon.

There were far-reaching consequences: Other Soviet leaders viewed Khrushchev’s risk-taking and withdrawal from Cuba as a loss of face and recklessness. This, together with erratic domestic policies, contributed to Khrushchev’s house arrest and removal the following year.

The withdrawal was indeed a clear sign of Soviet overreach and overconfidence—yet the Russians always viewed nuclear weapons not just as a symbol of power but as an ultimate war-fighting tool. The Russian high command still holds this view today.

A few years after the crisis, the Soviet Union and the U.S. began negotiating the Strategic Arms Limitation Talks (SALT) to avoid repetition of the Cuban Missile Crisis. The fear of mutual annihilation also begat détente—a Soviet policy of challenging the U.S. around the world, such as in Vietnam and Africa, while avoiding the ultimate confrontation.

The Soviet Union cynically used popular fear to create a nuclear disarmament movement and push for Nuclear Weapon Free Zones. Today, many, including President Obama, are talking about “global zero,” a world without nuclear weapons, despite rapid nuclear buildups by North Korea, Iran, Pakistan, and possibly China.

It is important to keep in mind the lessons learned from the Cuban Missile Crisis: Perception of weakness may trigger and overreach by a weaker actor. MAD at times appears as failing to deter. Diplomacy backed up by superior force may be crucial in thwarting a nuclear crisis.

After the collapse of the Soviet Union, the Russian and U.S. arsenals have been reduced significantly, but the mistrust remains. Massive stockpiles are ready for deployment at any minute. Despite four decades of arms control, consistent communication, and intensive diplomatic exchanges between the two countries, Russian leaders’ lack of trust in America and their Cold War mindset are still there. There is also a lack of trust among many U.S. citizens of our own leadership after President Obama’s comment to then-President Dmitry Medvedev about flexibility on missile defense.

However, 50 years after the Cuban Missile Crisis, it is Iran and North Korea, not Russia, that are pursuing nuclear weapons programs that threaten U.S. allies and, eventually, may threaten the American homeland itself.