[MACVSOG68]

So we can look forward to seeing minimal enforcement of our laws as usual?

Going after 20 million illegal aliens will take a massive effort unparalleled in this country. Sealing the border perhaps as massive. Anything meaningful will take a comprehensive approach by Congress. I don't see it happening, so we will likely have to be happy seeing 15 here, 20 here, while a hundred times as many continue to pour in.

[Jameison]

"Going after 20 million illegal aliens will take a massive effort unparalleled in this country"

True.
But no one is suggesting it can all be done today, in one fell swoop. But it can be done.
We did the Normandy landings, built the Panama Canal, after the French had given up, put a man on she moon, etc.
They all took massive unparalleled efforts.

But more importantly that 12 million is a straw man's argument, as Thomas Sowell put it so succinctly here:

"Yet another insult to our intelligence is saying that, since we cannot find and deport 12 million people, the only choice left is to find some way to make them legal. There is probably no category of law-breakers -- from counterfeiters to burglars or from jay-walkers to murderers -- who can all be found and arrested. But no one suggests that we must therefore make what they have done legal. Such an argument would suggest that there is nothing in between 100 percent effective law enforcement and zero percent effective law enforcement.
The reverse twist on this argument is that suddenly taking 12 million people out of the labor force would disrupt the economy. No one has ever said -- or probably even dreamed -- that we could suddenly find all 12 million illegal immigrants at once and send them all home immediately. This is another straw man argument. The real question is what we do with whatever illegal aliens we do find. Right now, there are various communities around the country where local officials have a policy of forbidding the police from reporting illegal immigrants to federal authorities."