The state I work in, like many others, have what is known as a “fusion center” that compiles a watch list of suspicious people.
Back in the 1980s an Arkansas State Trooper pulled a car over and was shot and killed by the driver. When the killer was apprehended, he claimed to be a "survivalist".
There was some freebie Federal anti-terrorism money floating around at the time, so Governor Bill Clinton of Arkansas set up an anti-terrorism task force. (survivalist == terrorist, at least in politics...)
They needed a way to identify terrorists before they struck, so they compiled a watch list of people who might be terrorists - all of Tony Alamo's "Sword of the Lord" whackjobs and parole lists from the Department of Corrections to start with. Finding the list too short, they primed it with other convenient lists... the state of Arkansas, for whatever mysterious reason, requires that the owners of all NFA machine guns that fire pistol cartridges to register them with the Secretary of State's office. I had to go to Little Rock to do it at the Secretary's office. They seemed a bit surprised; though Arkansas has (at least then) the highest per-capita number of NFA weapons in the USA, they'd only had a few people bother to fill out the state forms too.
You know what happened, don't you? They merged that list into the terrorist watch list too. I found out when I got pulled over for having a brake light burned out, and the cop went nuts when the dispatcher told him I was a terrorist.
Lists never go away. I still get mail addressed to the previous holder of my PO box... and I've had that box since 1979. We get mail addressed to my wife's father, who moved away in 1968. And those are just junk mail lists, not really good stuff like lists of terrorists. And I'll bet one US dollar that "terrorist" list is still floating around out there in Homeland Security's server farm, and another dollar that there's no indication as to where or why my name was added.
I already get the hairy eyeball at "security checkpoints" at state and Federal buildings. Fat old white guy, check. Short haircut, check. Beard, check. Sets off metal detector, check. Thousand yard stare, check. Bad attitude toward ridiculous clowns with badly-fitting uniforms and tin badges, check.
Sooner or later some TSA-like "instant check" will go into place on those buildings, and then the real fun will begin...
"We have a little list, oh yes we do..."