Nuclear Terrorism 101: Frequently Asked Questions

What is nuclear terrorism?
The detonation by terrorists of a yield-producing nuclear bomb containing fissile material. President Obama has described it as the “most immediate and extreme threat to global security.”

What is “fissile material”? Why is it needed for nuclear bombs?
Fissile material is matter that can sustain an explosive fission chain reaction (when an atom’s nucleus splits, releasing a massive amount of energy). Fissile material is the essential ingredient required to produce the chain reaction that causes a nuclear explosion.

What fissile material is needed to make a nuclear bomb?
Highly enriched uranium (HEU) or plutonium.

How much HEU would be required to make a nuclear bomb?
35 lbs (16 kilograms). The International Atomic Energy Agency’s “significant quantity” is 55 lbs (25 kg) of HEU, but this is often considered an overestimate. For an even simpler, “gun-type” design, more HEU (110-132 lbs; 50-60 kg) would be required.

What is the global stockpile of HEU?
3,168,000 lbs (1,440,000 kg) [275,000 lbs uncertainty each way].

How much plutonium would be required for a nuclear bomb?
18 lbs (8 kg).

What is the global stockpile of separated plutonium?
1,089,000 lbs (495,000 kg) [22,000 lbs uncertainty each way].

What is “nuclear security”?
Security measures for nuclear weapons, materials, and facilities to reduce the chance that nuclear weapons and materials could be stolen and fall into terrorist hands, or that nuclear facilities could be sabotaged.

What is “nuclear safety”?
Preventing an accident at a nuclear reactor, such as Fukushima.

What is “nuclear non-proliferation”?
Preventing the spread of nuclear weapons to additional countries.

What is a “dirty bomb”?
A dirty bomb is a device to spread radioactive material, for example with conventional explosives, to contaminate an area.

Is a “dirty bomb” a nuclear weapon?
No. A dirty bomb does not result in a nuclear explosion. It simply spreads radioactive material, and is sometimes called a “weapon of mass disruption” as its damage would be primarily economic and psychological.

How many nuclear weapons are there in the world?

How many nuclear buildings are there worldwide containing HEU or separated plutonium?

Is there enough missing fissile material to make a bomb? 
Yes. In 2005, the Director of the CIA testified that “there is sufficient material unaccounted for [from Russian nuclear facilities] so that it would be possible for those with know-how to construct a nuclear weapon.”

How could terrorists deliver a nuclear weapon to its targets? 
Through the same routes as drugs, illegal immigrants, and legal goods.

What could be the physical effects of a nuclear terrorist attack?
A 10-kiloton nuclear bomb set off at Times Square on a typical workday could kill half a million people and spread deadly fallout many miles downwind.

What would be the economic impact?
A study by the RAND Corporation estimated that the early, direct economic costs of a nuclear terrorist attack on a U.S. port would exceed $1 trillion, about 10 times the cost of 9/11. There would be immediate pressure to close all US ports to prevent another attack. Given that U.S. ports carry out 7.5% of all global trade activity, the consequences for the world economy would be catastrophic. Former UN Secretary-General Kofi Annan has argued that a nuclear terrorist attack “would stagger the world economy and thrust tens of millions of people into dire poverty,” creating “a second death toll throughout the developing world.”

Can nuclear terrorism be prevented?
Yes. The most important single step to prevent nuclear terrorism is to secure all nuclear weapons and fissile material, so they can’t be stolen and fall into terrorist hands. No fissile material available to terrorists – no nuclear terrorism. If all nuclear weapons and all nuclear weapons-usable materials were locked up as securely as gold in Fort Knox or treasures in the Kremlin Armory, we would have reduced the likelihood of a nuclear terrorist attack to nearly zero..