That's how ICE wants you to think about it, but they've tricked you. The rule that they actually implemented is that you must accept temporary detention while being scanned. If a random guy wants to take a picture of my face, he has every right to, but I in turn have every right to hide my face or flip him off and leave the scene before he gets a good shot. If ICE stops your car, and they don't trust your word that you're a citizen (or if you refuse to engage with them as is your right as a citizen), they will not let you leave until you've accepted a scan.
> Sad to see programmers, who are supposed to be so thoughtful, slip into panicked irrationality in the face of new technology.
This is not about technology. It's about civil, and ultimately, human rights. Society is crumbling fast and what you're concerned about are technicalities.