But Paul's position on immigration may be due to him genuinely thinking he is now being true to his principles.
After all, Libertarianism advocates open-borders. A true Libertarian supports such a policy only after all social programs have been abolished, so that people immigrate for opportunity rather than to take advantage of taxpayer-funded social programs.
However, what I call the "half-wit wing" of Libertarianism holds the point of view: What the heck. Social programs are never going to go away. So let's just open the borders anyway.
If you have doubts that Libertarians are capable of nonsensical thinking, just listen to Paul's incoherent string of left wing talking points on immigration.