This is the Cato Daily Podcast for Tuesday, April 10, 2012.

I'm Caleb Brown.

Mitt Romney likes the idea of spending at least 4% of our GDP on the military.

The question every Romney supporter should ask is,

where are those extra trillions of dollars going to come from?

Chris Preble, Vice President for Defense and Foreign Policy Studies at the Cato Institute, comments.

We've heard this term 4% for freedom, referring to a fixed share of our nation's GDP, not the federal budget, but GDP, to be devoted to defense.

Now up through, I guess as late as the 1970s and 80s, defense was really the thing that government did.

So it's reasonable perhaps from a perspective of defense may be crowded out by all of these other

important pieces of spending that are very popular and have a broad

constituency and perhaps the fear is we're going to, we,

the Defense Department providing for the common defense might get squeezed so from that perspective perhaps it's

understandable yes from that perspective it is understandable there's no

question that the the federal government's core role to defend the United States, our citizens, our interests,

has lost ground over the years to other government functions which are not core goals.

And there's not just libertarians who believe this, but conservatives and others believe this.

The problem with framing the discussion this way, however, is twofold.

First of all, defense strictly defined is a relatively easy thing to do for a country like the United States of America, which has wide oceans to the

east and west and relatively weak and friendly neighbors to the north and south.

And also we have nuclear weapons which are an additional benefit in terms of deterrence.

So it's a rather easy thing to defend the United States from traditional threats.

We haven't had to worry about traditional threats for a very long time, frankly.

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