Which weapons of mass destruction are no longer a threat and which weapons pose the greatest threat?
This is, of course, a matter of opinion.
My own opinion is that conventional nuclear weapons, owned and operated by countries, are much less of a threat than they once were. This is because none of the countries that has such weapons very likely to attack any of the others. This could change if Iran gets nuclear weapons or if North Korea gets more of them, but for the time being, the likelihood of nuclear war is relatively low.
The weapons that pose the greatest threat are those that are not well-secured. In other words, any WMD that belongs to a country that does not have good security procedures is a major threat. If a WMD (or even just things like spent nuclear fuel) fell into the hands of terrorists, they would be likely to use them (as with the sarin attack in Tokyo in the 1990s).
In my opinion, Depleted Uranium (DU) weapons use by the US, Britain and others are the most threatening weapons of mass distruction. Over 1,000 tons (tonnes) of DU weapons have been used in Iraq since the first invasion, "Desert Storm".
The following was taken from the following site:
Depleted uranium (DU) weapons were first used during the first Gulf War against Iraq in 1991. The Pentagon estimated that between 315 and 350 tons of DU were fired during the first Gulf War. During the 2003 invasion and current occupation of Iraq, U.S. and British troops have reportedly used more than five times as many DU bombs and shells as the total number used during the 1991 war.
While the use of DU weapons and their effect on human health and the environment are subjects of extreme importance the Pentagon is noticeably reluctant to discuss these weapons. Despite numerous calls to specific individuals identified as being the appointed spokesmen on the subject, not one would answer their phone during normal business hours for the purpose of this article.
Dr. Doug Rokke, on the other hand, former director of the U.S. Armyís Depleted Uranium Project, is very willing to talk about the effects of DU. Rokke was involved in the "clean up" of 34 Abrams tanks and Bradley armored vehicles hit by friendly fire during the 1991 Gulf War. Today he suffers from the ill effects of DU in his body.
"A flying rod of solid uranium 18-inches long and three-quarters of an inch in diameter," is what becomes of a DU tank round after it is fired, Rokke said. Because Uranium-238 is pyrophoric, meaning it burns on contact with air, DU rounds are burning as they fly.
When the DU penetrator hits an object it breaks up and causes secondary explosions, Rokke said. "It's way beyond a dirty bomb," Rokke said, referring to the terror weapon that uses conventional explosives to spread radioactive material.
Some of the uranium used with DU weapons vaporizes into extremely small particles, which are dispersed into the atmosphere where they remain until they fall to the ground with the rain. As a gas, the chemically toxic and radioactive uranium can easily enter the body through the skin or the lungs and be carried around the world until it falls to earth with the rain.
AFP asked Marion Falk, a retired chemical physicist who built nuclear bombs for more than 20 years at Lawrence Livermore lab, if he thought that DU weapons operate in a similar manner as a dirty bomb. "That's exactly what they are," Falk said. "They fit the description of a dirty bomb in every way."