But the simple argument seems compelling: The US with 27% of world product has about 46% of world military spending (up from 40% in 2000). Yet our "defense" needs are few, as we are rich, isolated, have friendly neighbors, and haven't been invaded for centuries. And it is hard to see how "offense" spending at this level could possibly be cost-effective.
This reminds me of an interesting moment during my recent interview with Bryan Suits*. When we were on the subject of anti-foreign bias, Suits suggested that Ron Paul exemplified it because of his opposition to military intervention in other countries. I disagreed. In my view, anti-foreign bias makes us over-estimate foreigners' ability and desire to do us harm, and therefore normally encourages military intervention.
* To hear the podcast, go here scroll to October 16, and and click on Listen.