This is the Cato Daily Podcast for Monday, December 21st, 2015. I'm Caleb Brown.

The debate over immigration has taken a decidedly negative term from debating how many immigrants

to allow into the country and how many more visas the

U.S. should grant.

The debate now centers on banning for a time immigration altogether.

Cato's Alex Narasta and George Mason University's Brian Kaplan sat down with me to discuss the troubling new debate last week.

What do you think is the worst proposal that has received any traction that's been put out there so far.

Alex would know a lot better than me.

I think probably the worst proposal is a total moratorium on all immigration

just to make sure that there's no potential security threat at all going forward.

And leaving aside the problems that that would pose logistically for employers in the United States, what are the estimates for economic costs of such a proposal?

So I took a look at a paper written by Ben Powell at Texas Tech University,

he tries to estimate sort of the annual cost of a total moratorium

on immigration and he comes to somewhere around $200 billion annually, annually to the U.S. economy.

So looking at that going forward, the number of terrorists who have committed a

tax since 9-11 about 73% of them have been immigrants. So like assuming that

70 and the terrorist tax per year there's about three casualties per year and

take a look at the cost estimate it's about a hundred million dollars for all of

those attacks per year at like the uppermost bound so an immigration moratorium at best would reduce these costs by

73 million dollars per year at a cost of 200 billion dollars a year to the economy

under very generous assumptions.

So there's really just no way that this makes sense

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