How Big Is The Nuclear Threat?

The United Kingdom’s Boris Johnson announced a plan to increase the size of the cap on the UK’s nuclear weapons stockpile. The outcry has been significant with regard to international law and the Treaty on the Non-Proliferation of Nuclear Weapons. Iran called the move hypocrisy. I am more interested in the numbers.

The UK government conducted an integrated defense review and concluded the nuclear arsenal should be lifted by 40% to 260 warheads. The UK had previously committed to cutting its stockpile to 180 warheads by the mid-2020s, but the government says the review requires a change in recognition of the “evolving security environment” including the developing range of nuclear, biological, chemical, and doctrinal threats”. The argument is to show a deterrent. More on that shortly.

In 1986, there were more than 70,000 nuclear weapons. Since then, there has been a significant reduction but there still remain nearly 15,000. The numbers vary depending on the source but roughly speaking the United States has about 7,000 and so does Russia. Eight other countries including the United Kingdom, France, China, India, Pakistan, North Korea, and Israel collectively have about 1,000 weapons.

Two nuclear weapons have been used in the course of warfare, both by the United States near the end of World War II. On August 6, 1945, the day after I was born, a bomb code named Little Boy was detonated over the Japanese city of Hiroshima. Three days later, on August 9, a second bomb code named Fat Man was detonated over the city of Nagasaki. Combined, these two bombings resulted in the nearly instantaneous death of approximately 200,000 people. The yield of the blasts was 15 kilotons and 22 kilotons. That was two nuclear weapons. Today, the world has about 15,000.

A typical nuclear weapon today weights about 250 pound and has a yield of up to 150 kilotons, ten times the bombs which destroyed two cities and 200,000 people. The Russians have a weapon known as the Tsar Bomba. It is the most powerful nuclear weapon ever created and tested. The bomb is 26 feet long and 7 feet in diameter. It weighs 60,000 pounds. The yield is equivalent to 50 million tons of TNT 3,000 times greater than the 1945 bombs. When the Russian bomb was tested, the mushroom cloud could be seen from 100 miles away. The crown of the cloud was 40 miles high. The United States and Russia each have the power to render Earth an uninhabitable nuclear wasteland.

Unfortunately, the technological barriers to going nuclear are low. Barry McCaffrey, a retired U.S. Army four-star general, said,

The science is available on the internet. With less than 20 lbs. of donated, stolen or manufactured highly enriched uranium, or a plutonium device, even primitive Libya under Gen. Muammar Gaddafi’s rule was close to going nuclear. There are easily some 30 nations that in less than five years, with the help of a rogue power, could cross the nuclear threshold.

Although the total arsenal has declined, it likely remains an irreversible existential threat to U.S. national security. General McCaffrey said,

We are stuck permanently with deterrence as the central pillar to prevent their future use. There is no going back. However, we can dramatically lower the chances of a future Armageddon through smart arms-control negotiations and international diplomacy.

I hope our political and policy leaders clearly understand the horrific magnitude of the devastation which would result from a nuclear exchange. General McCaffrey said that an all-out exchange with the Russians would be over in about 30 minutes, along with most life in the two nations. Some experts believe North Korea is developing a one-megaton weapon which, if they could detonate it over Seattle or Honolulu could kill 50% of the populations within a five mile range. Kim Jong Un may now have 30 to 60 nuclear devices and a prototype of an intercontinental ballistic missile. He is also believed to have the initial design for a sub-launched nuclear missile. An even bigger fear is North Korea making their nuclear technology available to terrorists.

Despite the gloom and doom possibilities, there is hope. The nuclear threat initiative ( is a non-profit bipartisan organization focused on protecting lives, the environment, and our quality of life now and for future generations. It is working to prevent catastrophic attacks with weapons of mass destruction and disruption, nuclear, biological, radiological, chemical and cyber. I hope the free world will put our brightest arms-control minds to work on multiple approaches to the constraint and reduction of the nuclear global threat.

General McCaffrey outlines some important steps,

Step one should be a U.S. unilateral presidential announcement of “No First Use” in the first year of the next [now current] administration. Step two should be the U.S. unilateral removal of our 150 largely useless B61 gravity nuclear weapons in Europe. Step three would be congressional binding legislation to eliminate the president’s “sole use” authority to employ nuclear weapons.

The hawks will argue the three steps will reduce the U.S. nuclear deterrent capability. General McCaffrey has a lot of experience with issues surrounding nuclear weapons, and he believes that would not be the case. He further believes our sea-based nuclear capability for a massive second strike would create a very clear deterrence. Finally, the General believes we need to freeze in place the further global expansion or modernization of nuclear weapons with verifiable international monitoring. I hope the new administration gives a very high priority to make this happen.