The above types of people (illegals, Afghans, Antifa) cannot do office work nor crunch numbers. If you send them on a raid, Americans would take them as criminals and scare them off their property with their hardware. If it ever came down to it, a big disaster all the way around. Unless you actually want to slaughter, it is more cost effective to just collect taxes "as usual." And how do you know said illegals won't just randomly gun people down everywhere? Way way too messy of an idea.
The above types of people cannot do office work nor crunch numbers. If you send them on a raid, Americans would take them as criminals and scare them off their property with hardware.