A massive deportation campaign is not only logistically impossible, it would also cost at least 80 billion in tax payer money. In the process of doing so, you would bring the economy to a screeching halt.
So if Trump can’t actually go through with his promise of a massive deportation effort due to the reasons listed above, plus the massive legal challenges he would have to overcome, what is he gonna do in response?
My guess is he’ll take it out on legal immigrants. Make their lives a little bit more difficult just to appease his base.