It's a infrastructure ready-made for abuse: for tracking and surveilling "unAmerican" folks, or for hassling, harassing, or even restricting the travel of "subversive" types who are not in favor with the government power. Has the government gone that far yet? No. But it's a basic principle of good civic hygiene that you try to avoid creating a system pre-built for pushbutton civil liberties infringements. The temptation to abuse the system is so great, that mere existence of such a system is a danger to freedom. It makes it too easy for a future government inclined towards a police state to impose, in the future, restrictions that we would find abhorrent. I don't want to set up a situation that would allow an evil government to seize power, and hold it. The best way to prevent that is to avoid creating an infrastructure that makes those abuses as easy to set up as the "flip of a switch".

I also hate the precedent. IDs are spreading all over, and the argument I hear is "well, you have to show ID to fly, so why shouldn't you have to show ID to (X)?", where (X) can be things as crazy as "get on a public bus and ride across town". The photo ID requirement creates a "papers, please" society where the public is habituated to demands to see their ID, and that's not a good thing.

Oh, yeah? How do you know? For all I know, airlines might be saving all PNRs. (You might say that they didn't save the "ID", but when they check that the name on your ticket matches the name on your ID, and then save the name on your ticket in a database, well, the difference is academic.)

Keep in mind the recent revelations that AT&T has a giant database with records about every call that has been placed through their network over the past few decades. A decade ago, would you have guessed that AT&T was recording all this information? Would you have guessed that AT&T would turn it over to the NSA to allow them to do data mining, even of US citizens, even lacking probable cause or a warrant or court oversight? How do you know something similar can't happen to the airline databases? How do you know it hasn't already happened? I don't think it is overly paranoid to be concerned that this information could be abused.

I want to retain control over my personal information, and I don't appreciate a government that forces me to relinquish control for no good reason.

Well, not quite. I have to tell my real name to the airline. That's not flying anonymously. That's very different from a system where I can make up any name I like to put on my ticket, and fly without getting hassled about ID.