I'm assuming your question concerns a future "libertarian utopia." For the next few years  the government will still be in the business of granting visas and naturalizing new citizens, and murderers will kept out. Or at least <i>most</i> murderers will be kept out; murderers with friends in high places or with buckets of drug money will still get through.

We should move in the direction of that "libertarian utopia" because the economic advantages of millions of hard-working immigrants vastly outweighs the harms of a handful of murderers. That may sound callous, but if you think about it, it's true. We can turn America into a police state to keep one murderer out, and then the standard of living of millions is dramatically reduced. If we open the borders and the murderer gets in, the statistical probability of YOU being murdered is very small, but you and millions of other people gain better lives. More people is good. It means more jobs can be created. More human potential will be unleashed. Economic development will increase.

We should also move toward that "libertarian utopia" because it's the right thing to do, and we have no right to pray "God bless America" if we're not doing the right thing. A bureaucrat in Washington D.D. has no ethical or moral right to tell Jones in L.A. that he cannot hire Gonzales, cannot rent to 


There are no immigration laws between Missouri and Oklahoma. How do we here in in Missouri keep murderers from Oklahoma out?