Radiological.

This is coolbert:

Of the three weapons of mass destruction [WMD], I would think that the radiological weapon [dirty bomb] would be the weapon of choice for terrorists.

Too much trouble to get your hands on a real nuclear a-bomb type weapon.

And too much danger too. If the U.S. finds you have your hands on one, the heat would really be on then.  

Chemical weapons are too difficult to make in quantity, transport, store, use, and are just down right dangerous to possess in their own right.  

Biological weapons are too dangerous to possess as well, can backfire and come back to infect you as well, and if the U.S. knows you have them, as with the a-bomb, the heat will be really put on then.

So we are left with the radiological weapon.

Also called the "dirty bomb" or the "poor man's nuke". Take radioactive material and place that material with a conventional explosive of considerable force. Of considerable force, but not having to be huge in size.

This radioactive material can be waste product of the nuclear industry, the medical industry, the nuclear power industry, or sundry radioactive materials such as found in smoke detectors.

It seems that cesium-137 is the ideal candidate, the type of radioactive material used in hospitals.

This conventional bomb, when exploding, will throw a huge cloud of dust and debris into the air, hopefully placed upwind of the downtown area of a major city. This cloud of dust and nuclear particles mixed in will drift over the downtown area and settle. Creating an irradiated area that will be dangerous for the public.

Both in the short and long term this will pose a significant problem for residents that live and work in the area.

A decision will have to be made as to what to do after the radioactive debris settles.

Evacuate the area, clean, and continue the march, or evacuate and have the area declared off limits.

To do the latter would entail economic disaster on the order of billions of dollars, if not more [trillions of dollars in real estate and property value?].

 People subjected to the radioactivity would not have health problems in the short term, as least for the most part not, but would face health problems in the long run in the form of increased cancer and related illnesses.

The main goal of the terrorists such as Al Qaeda with the radiological weapon would be primarily economic disruption and terror.

To give you just one example of how this has been done in the past, one IRA bomb in London went off without one person losing their life. But $1 billion dollars worth of windows in high rise buildings were blown out in the process. This all from one bomb. And non-radiological too. The economic cost and insurance costs for the future would make anyone, government or otherwise, sit up and take notice and would cause these entities to reconsider their options.

Now, I would bring attention to a story that occurred about ten years ago now.

A kid, fourteen years old, set out to build his own radioactive pile.

To do this he purchased about 1000 smoke detectors for a measly price from some company and removed the radioactive elements and enriched these elements through some sort of electron beam bombardment [to read about this click here].

This was all done by a kid without any sophistication and equipment that was homemade and primitive. But what he did worked. The kid was able to obtain the necessary radioactive material legally and was able to enrich the material so that it had a pretty good radioactivity to it, suitable for his purposes.

This demonstrates that a determined person wanting to build a radiological device would be able to do so at leisure and with confidence that they could do so. Scary stuff!!

My own personal perception of what would occur if a dirty bomb is exploded upwind of a major American city or cities, is that the clean up would occur and the order would be given to continue the march. Continue business as best as possible as it was before the bombing, and hope for the best. Let mother nature continue the clean up [rain] for years into the future, monitor the public for health difficulties and "que sera sera".

coolbert.