The more I think about TIA, the more ludicrous the notion gets. I get very few telemarketing calls and very little junk mail. Why? Because I try to pay cash as often as possible (the exception being gasoline, it's very convenient to pay at the pump, but gasoline purchases only tell someone a pattern of roughly where I travel). It won't be too hard for terrorists to avoid leaving a significant data trail - the reason so much data is available for most Americans is that they don't care how much data they leave in their wake. But terrorists will care.
And much of the data that the creators of TIA want simply isn't available legally. For example, one item TIA wants to trace is gun purchases - but if someone makes a $400 charge at Wal-Mart, did they buy a gun or a Stairmaster? TIA would need to tap into the background check database, something they are prohibited by law from doing. So when they talk about what they want to capture, some of the data is commercial available, but much of it will require legal changes that I will not support.