The argument is that it is possible that Iraq might have weapons of mass destruction at some time, and might launch a suicidal attack against the rest of the world, and that this justifies a pre-emptive strike by the USA against that country.

That is an argument that would justify a pre-emptive strike against any country on the planet that a US government might at any time choose to target.

One thing for certain, if Bin Laden is alive he must be praying for that attack on Iraq to take place.