I'm not sure if that's a good idea to start as a trend. It'd make it easier for actual ICE agents to hide in plain sight.

I don't think making it easier for state-endorsed terrorism to fly under the radar is a good strategy for stopping it. If you physically intervene with every terrorist-fashioned individual you see you're much more effective when they're all actually ICE and not just trolls. And I'd very much recommend that course of action.

Some places (like part of Long Island, naturally) have made it illegal to wear a face mask.

Yeah, that way you could kidnap whoever you want and look legit doing it.

To what end would you be imitating those fascists?