What I find interesting about the DACA debate, not that I know much about it other than what I read here and elsewhere, is that it seems like a manufactured issue of the week to me. Trump needs to keeps his base on an emotional high, lest they stop and analyze things too closely, so let's chase after a few foreigners. It must help things if they're not white too.
Of course a rational legal immigration policy is required, you can't just let people walk in at their leisure, but after they've been in for a while and are integrated and are working and contributing to the economy, how is anyone better off by wasting resources chasing them down? It's not as if there isn't precedent for selective prosecution. The authorities don't chase after and arrest EVERY prostitute or drug dealer, and they certainly don't spend much time chasing after biker gangs and the mob, from what I can tell. If Trump and others stopped foaming at the mouth about this, the entire issue would disappear in 2 news cycles because, really, it does not matter to anyone, in the sense that its importance rounds to zero. The emotional support for it is manufactured. It's got "fake" written all over it.
It's not like the US doesn't have bigger more important problems to address. But those things require work, and it's easier to whip up a frenzy about other things. For instance, how does reducing taxes square with rebuilding a crumbling infrastructure. I don't see many frenzied battles about that. Trump must be following KISS thinking. Priority one is keeping the base energized for the 2020 vote, I guess, as re-election seems to be what politics is all about now.