According to Baltimore Sun, the NSA developed a program for the purpose of analyzing communication data in the late 1990. Unlike what they are doing now, the old program was legal and protected the privacy of Americans - and worked better.
They rejected it in favor of a system that was illegal, unnecessarily intrusive and didn't work so good.
But if you're Bush, you ALWAYS prefer the option that's illegal, intrusive and innefficient. I honestly think it gives the man the sort of rush that a teenager gets when he gets away with something.