Here’s the biggest problem about the metadata program: It doesn’t actually help national security. It’s a false tradeoff. Collecting everybody’s — literally everybody’s — phone metadata is useful if you want to do data mining. “Data mining” is a fancy term that gets thrown around, but refers to a specific approach: trying to make sense of very large sets of data by trying to find statistical patterns within them. You try to associate terrorist cell activity with a particular data pattern, and then try to match that pattern with other patterns in the data.

The problem with this approach to counter-terrorism is that it works best under certain conditions — specifically, when the nature and type of data are not changing over time, when the data are complete and clean, and when you know what you are looking for. In reality, the conditions for finding terrorist activity (or any kind of criminal activity) are exactly the opposite.

Osama Bin Laden wasn’t found using data mining. He was found using a combination of old-fashioned detective work and, yes, data analysis — analysis of specific data sets, of the kind that warrants are useful for (if we were looking for a domestic enemy, as Bin Laden was not).

So it wasn’t just the civil liberties abuses that the Snowden documents revealed, it was the ineffectiveness of the NSA.