Found the WMD. It is here.

A 10-megaton nuclear weapon (The current U.S. warhead strength) creates an explosion equivalent to the detonation of 10 million tons of TNT--from less than 200 pounds (90 kg) of nuclear fuel. Pressure waves emanating from the blast would exceed 30 pounds per square inch and generate winds in excess of 700 miles per hour (1,125 km/h). Such winds could knock down steel-and-concrete buildings with ease. Even 20 miles (32 miles) away, the blast would shatter windows and uproot trees.
The temperature around the blast would rise in an instant to more than 18 million degrees Fahrenheit (10 million degrees Celsius)--hotter than the sun. Everything in a 2-mile (3.2-km) radius would be vaporized. Further out, materials like glass and steel would melt. Further still, combustible materials would ignite and produce innumerable fires. Even at distances greater than 20 miles (32 km), humans would suffer serious burns from the flash.
And when the dust cleared and the fires were out, the bomb's most insidious effect would remain: radiation. Radiation is all around you. It bombards you every moment of your life, everywhere you go. Don't panic, though. Radiation is simply traveling energy, and most of it is harmless. But some forms, like ultraviolet light and X-rays, are harmful if you're exposed too long. Radiation like this, called ionizing radiation, contains enough energy to break down chemical bonds in substances that absorb it.
Radioactive elements like uranium and plutonium emit, among other things, gamma rays, packing 10,000 times more energy than visible light. Gamma rays can pass right through humans, penetrating tissues and ionizing atoms in your body. This leads to massive cellular damage, resulting in system-wide "radiation sickness" and, with enough exposure, death.
Although damage from the blast, heat, and even radiation burns may heal over time, the ionizing damage done to the DNA in human cells will remain. Sooner or later, the body's own replication of damaged DNA leads to the final danger of a nuclear blast: cancer, mutations, and a host of genetic abnormalities. These last casualties can take years, or even decades, to occur.