(THE CONVERSATION) During the 1960s, the Soviet Union and the United States came close to war because of the Soviet attempt to plant nuclear weapons in Cuba, 90 miles off the coast of Florida.

People in the United States feared a nuclear war. Children practiced nuclear drills hidden under their desks. Families have built nuclear bunkers in their backyards.

But later in the 20th century, nuclear war became less likely. Countries have pledged to reduce their stockpiles of nuclear weapons, or pledged not to pursue nuclear weapons in the first place.

Now, after decades of progress in limiting the buildup of nuclear weapons, Russia’s war on Ukraine has sparked renewed nuclear tensions between Russia and the United States.

On February 24, 2022, Russian President Vladimir Putin threatened that any country that interfered in Ukraine would “suffer worse consequences than you have faced in history.” Many experts and observers have interpreted this as a threat of nuclear attacks against the defenders of Ukraine.

A single nuclear weapon today in a major city could immediately kill between 52,000 and several million people, depending on the size of the weapon.

Understanding these new threats requires understanding efforts to reduce the number of nuclear weapons, prevent the spread of nuclear weapons to new countries, and the development or stockpiling of nuclear weapons in different countries.

I have worked and researched nuclear non-proliferation for two decades.

Convincing countries to reduce their stockpiles of nuclear weapons or to give up the pursuit of this ultimate weapon has always been extremely difficult.

A history of non-proliferation

The Soviet Union, United States, United Kingdom, France, Israel, and China had active nuclear weapons programs in the 1960s.

Countries have recognized the risk of nuclear war in the future.

Sixty-two countries initially agreed to what was called the “Grand Bargain” in 1967, a core part of the Treaty on the Non-Proliferation of Nuclear Weapons. One hundred and ninety-one countries eventually signed this treaty.

The agreement prevented the spread of nuclear weapons to countries that did not already have them in 1967. Countries with nuclear weapons, such as the United States and the United Kingdom, agreed to end their race for nuclear weapons and to work towards eventual disarmament, that is to say the destruction of all nuclear weapons.

This historic agreement laid the groundwork for agreements between the United States and the Soviet Union to further reduce their nuclear weapons and their means of delivery. It also prevented other countries from developing and testing nuclear weapons until the end of the Cold War.

Israel, India and Pakistan never joined the agreement due to regional security concerns. They all now have nuclear weapons. North Korea withdrew and developed nuclear weapons.

Other countries have given up their nuclear weapons or programs to develop them.

Some successes

Since the Cold War, major advances have been made to prevent countries from acquiring nuclear weapons and to drastically reduce stockpiles of nuclear weapons.

The global nuclear stockpile has been reduced by 82% since 1986, from a peak of 70,300, with almost all the reductions in the United States and Russia, which held the largest stocks at the time.

Globally, there are approximately 12,700 nuclear weapons today, of which about 90% are held by Russia and the United States, or between 5,000 and 6,000 weapons each.

There are several other nuclear-armed countries, and most of them have a few hundred weapons each, including China, the United Kingdom and France. New nuclear countries like India, Pakistan and Israel have about 100 each, while North Korea has about 20.

Beginning in the late 1960s, countries entered into more than a dozen legally binding agreements, known as treaties, that limited the acquisition of nuclear weapons by new countries and prohibited nuclear weapons testing. nuclear weapons, among other measures.

But they did not reduce the number of nuclear weapons with short-range missiles.

No agreement covers these weapons, which could also cause large-scale destruction and death. Russia’s short-range weapons could quickly destroy much of Europe.

The United States and Russia have always worked together to reduce nuclear weapons, despite numerous proxy wars in Korea, Afghanistan and Vietnam at the same time.

They have also jointly pressured Iran, North Korea and Libya to give up their efforts to develop nuclear weapons, with some success in Iran and Libya.

US-Russian cooperation declines

The US-Russian commitment to nuclear weapons changed when Russia forcibly annexed Crimea from Ukraine in 2014.

Russia built land-based missiles in Kaliningrad, a Russian enclave in the middle of Eastern Europe, in 2014.

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The United States and NATO then accused Russia of violating a 1987 nuclear agreement on short- and medium-range land-based missiles. From Russia, these could travel between 500 and 5,500 kilometers (311 to 3,418 miles), hitting targets as far away as London.

The United States also terminated this agreement in 2019 due to Russian violations. However, there are no international nuclear agreements in Europe.

Yet the main strategic nuclear arms agreement, known as New START, remains in place and will remain so until at least 2026.

Impact of the war in Ukraine

While Putin has failed to follow through on his threat of a nuclear strike, the potential for a nuclear strike has meant that the US and NATO response to Russia’s attacks on Ukraine has landed far from direct engagement.

This is the first time that nuclear threats have been used by a country that has invaded another rather than defending a country.

It also marks a step backwards in international work to reduce the threat of nuclear war.

This article is republished from The Conversation under a Creative Commons license. Read the original article here: https://theconversation.com/russia-is-sparking-new-nuclear-threats-understanding-nonproliferation-history-helps-place-this-in-context-180533.