It seems the conservatives who are most skeptical of immigration reform don’t oppose the merits of Rubio’s framework, so much as they simply refuse to believe it would ever be enacted or enforced.
In other words, they simply don’t trust that the law will be obeyed. They believe Democrats can do whatever they want, and the best conservatives can hope for is to slow them down and not give them any ideas.
This is very destructive for democracy. And the sad thing is that their cynicism and paranoia isn’t entirely unfounded.