Society has changed. Laws practically didn't exist back then, should we go back to a near lawless society? Should we bring slavery back? Should we prevent woman from working, driving, voting?
In any case it’s not the deportation that most people necessarily have an issue with, it’s how they go about doing it. They even killed citizens in the process. Obama deported quite a few.
“Law never made men a whit more just; and, by means of their respect for it, even the well-disposed are daily made the agents of injustice.” — Henry David Thoreau