Nuclear weapons are humankind’s most fearsome creations.

In a matter of minutes, one nuclear-armed nation can level dozens of cities, spread radioactive fallout for hundreds or thousands of miles, and wreck Earth’s climate.

Most people are familiar with the basics: Slap together enough uranium or plutonium and – kaboom! – you have a nuclear blast.

But the details of how these complex devices are made, delivered, and controlled can make the difference between keeping the peace and sparking a cataclysm.

It doesn’t help that there’s more than 60 years’ worth of convoluted terminology surrounding the complex policies and politics of nuclear weapons.

There are words like isotopes, fission, tritium, and yellowcake; abbreviations such as HEU, LEU, SSBN, and CVID; and the subtle yet striking difference between uranium-235 and uranium-238.

As President Donald Trump and his administration try to continue talks with North Korea over its nuclear weapons program – an effort could take years to pan out and is guaranteed to get very, very complicated – we’ve defined some of the most important (and misunderstood) words, phrases, and acronyms here.

Nuclear weapon

A conventional explosive device rapidly burns up a chemical to cause a blast. A nuclear weapon, meanwhile – such as a bomb or warhead – splits atoms to release millions of times more energy than chemical reactions.

Yet the term “nuclear weapon” can also refer to a vehicle that’s able to deliver a nuclear attack, such as missiles, fighter jets, stealth bombers, and truck-like mobile launchers. (If flying dinosaurs were alive today and trained to drop nuclear bombs, the creatures may be considered nuclear weapons.)

During weapons inspections like the ones between the US and Russia, nuclear warheads are actually concealed with a piece of cloth; it’s the vehicles, missiles, and launch or bombing bays that are the focus. Without them, a warhead can’t get anywhere quickly.

Intercontinental ballistic missile (ICBM)

An ICBM is a space rocket that can launch a destructive device on top and carry it from one nation to another in a high arc.

Technically speaking, an ICBM is any missile capable of delivering one or more warheads from more than 3,415 miles (5,500 kilometres) away. The missile silos in the US in which they’re stored are sprinkled around the country, with most stationed in middle America.

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