Well, the problem is that you can't have a "guilty people only" filter on a data trawling system. You have no idea who the guilty people are, that is why you a

Well, the problem is that you can't have a "guilty people only" filter on a data trawling system. You have no idea who the guilty people are, that is why you are trawling the data. So, I guess what you have to ask yourself, is if the fourth amendment is worth sacrificing in order to catch drug dealers. I don't think it is, and I hope most Americans agree. <edit> replacing drug dealer with terrorist doesn't change my view on the matter</edit>