The major effect of the new immigration order is not to increase the number of deportations. It is to give border agents more discretion. Previously protected people (for example, those who committed minor crimes) may now be deported. But the financial and human resources available for deportation remain the same—unless Congress is willing to appropriate tens of billions of dollars in additional money for enforcement, which it hasn’t, not yet, and—in my view—probably won’t. This means that the number of deportations will not increase, or not significantly.
The effect is the reverse of what conservatives normally seek from agencies. In the case of environmental protection, health and safety, financial regulation, and the like, conservatives typically complain that regulators enjoy too much discretion. “Just tell us the rules,” they say. They argue that discretionary regulation creates excessive uncertainty, which interferes with planning, and subjects them to blackmail from regulators with political agendas.
Does this argument apply to immigration? Yes, it does—at least, if immigration authorities carry through the ban as promised. Previously protected people now face greater uncertainty—they might be deported whereas in the past they knew they would not be. But if so, it follows that classes of undocumented aliens who previously faced deportation with a high probability now face a lower probability. The major such class comprises those who have committed violent criminal offenses. Do we really want them to worry less about deportation?
I also suspect that it is cheaper to deport violent felons than ordinary people. A violent felon is deported after he completes his prison sentence. He’s loaded on a bus or plane and off he goes. By contrast, non-criminals will be able to obtain continuances and make due process challenges, which are costly for the government to counter. In some cases, they will be held in detention centers—an additional cost that was not incurred under the old system. There is a reason that not only Obama but Bush mainly deported the criminals.
Which makes me think that border agents will use their new discretion to do exactly what they did under Obama and Bush: deport the violent criminals while letting the others stay in the country. The overall effect, then? PR.