[MACVSOG68]

We don't stop prosecuting criminals just because it would send the number of felons above a certain percentage do we? Why do anything different for illegal foreign invaders?

Heck, I didn't know rounding up 20 million illegals was that simple. But I hope you can do it without legislation.

[Jameison]

"Heck, I didn't know rounding up 20 million illegals was that simple."

Neither simple nor easy.
Can it be done with enough determination, political will, enough brain power, resources etc put into it?
Yes.
Does it mean every single one of the 12 million have to be deported before its a success?
Nope.
That has never been the way we measure success in any policing work in this country.