This is still not fully supported by law. It is becoming normalized indeed, especially by the current admin. Let's hope this is not going to become widely used or that it doesn't stay permanently, eg. it gets at least restricted to some type of crime by future administrations.
There are many unresolved gray areas around what exactly the 4th amendment permits in the way of what United States v. Knotts called "dragnet-type law enforcement practices". Knotts suggested they might not be permitted, even if they were made up of permissible individual parts, but didn't elaborate. More recent case law has held, for example, that cell phone companies turning over large quantities of records is a 4th amendment search requiring a warrant, even if they do it voluntarily (https://en.wikipedia.org/wiki/Carpenter_v._United_States). Most other types of dragnets haven't been litigated enough to have solid caselaw on their boundaries afaik.
I don't know if it's likely a court will do anything about this particular program, but from what I've read I don't think 4th amendment scholars think this area is at all settled.
From what I understand, this isn’t so much a “dragnet” operation involving combing through mass quantities of records on demand; it’s more like “this person is in public in my field of view, and I want to know who they are.”
More importantly, though, the cases so far have focused on the investigative activity that follows once a suspect has been identified. Here, we’re talking about de-anonymization: identifying one or more individuals who occupy a public space. AFAIK, the Court has never established a reasonable expectation of privacy of one’s identity in public. That will be a steep hill to climb.
I don't have to identify myself to police where I live. That's why, in my opinion, this is an unreasonable use of technology. I'm not sure what qualifies under the fourteenth but force-ably identifying me when I don't want to be and not required to seems unreasonable.
In the U.S., current law holds that for a law enforcement officer to stop and request identification, the officer needs at least some sort of articulable basis for doing so (Terry stop). The key word here, though, is “stop.” Electronic surveillance of a public space, though, involves stopping nobody. It’s not clear to me that passive identification involves either a “search” or “seizure” within the traditional meaning of the 4th Amendment. We’ll see what the courts think, though.
While you are correct that some states do regulate facial recognition, all they can do is regulate their own law enforcement and private entities doing business there. They cannot regulate the federal government (ICE and CBP are federal agencies).
Ah, what's good is law when the branch^W [after rereading about it, executive power is given to one] person tasked with executing laws is... lawless?
The notion that future administrations won't be offshots of the current regime (again, why do you think laws regarding democracy, like fair elections, will be upheld?) is also too hopeful.