Thats totally wrong. The war on drugs has a demand side of it, which changes everything, and I don't see Colombian cartels murdering 7000 US citizens. They are two totally different things. The drug trade is so huge that it is able to bribe whole government systems into looking the other way. Terrorism can only frighten people for so long.
The point about there being a demand for drugs and not a demand for terrorism makes the arguments that they are the same collapse like the house of cards.
OK you want demand? How about some percentage of the 1 Billion Muslims in the world. They demand it don't they? Bin Laden has a constituency for his actions does he not? Or is he just some psychotic like ChArles Manson. Those who won't see won't see.