The scenario outlined in the article did not describe a fast moving armored column (how are they going to position armor near Baghdad?) I took it as a stationary force intended to essentially lay siege to Baghdad. In that case, the delivery mechanism is any of the five aerosol generators we know Saddam has purchased from the French (see Germs: Biological Weapons and America's Secret War), a truck, and prevailing winds.
In addition, during the Gulf War, the US emphatically stated that it would retaliate with nuclear weapons if Iraq used chemical or biological weapons against the coalition forces.
That is really our only deterrent against his use of the WMD he already has. However, this will be a classic case of winning the battle and losing the war. Our use of nuclear weapons will result in the immediate cessation of any further prosecution of the war against Islamists. The knee-jerk left will shut it down in hand-wringing America-hating fury.
Iraq is only the first step in the long war ahead of us. It needs to be a clean quick kill.
Armoured columns are only needed to advance into Iraq and secure vast stretches of territory.
Once all the territory surrounding Baghdad has been secured, a seige does not need to included a campout outside the city gate as was the case during the Trojan War.
A seige of Baghdad can be effected by securing all roads into Baghdad from a point 20, 40, 50 or 100 miles away and using airpower to make any vehicle going into Baghdad a burning hulk by the side of the road.
In regards to unleashing bio-weapons with aerosol generators, Saddam would soon learn what both sides of the World War One Western Front learned when they first started using chemical weapons.........Those d@mn winds have a nasty habit of changing on you and bringing that stuff right back at you.
That would be an ironic end to old Saddam. :-)