Fuchs
Conscription is more expensive (monetary costs + human costs) than a volunteer army and thus suboptimal from the national point of view (,too).
AmericanPride
(...)in GDP or military expenditures per capita(...)defense spending(...)increased spending
Furthermore, a discussion of a specific choice does not allow global developments to be taken as an argument as if there was a proved causal relationship.

Now try to understand. I did neither write about individual soldiers nor only about money. I wrote about general welfare - the country's general well-being.

I do harm to you when I force you to do something disgusting by pointing a gun at you. Such an action would not have any fiscal impact or GDP effect. Now imagine I'd do it to four million Americans every year. Something really, really disgusting. Four million times a year.
The general welfare of the U.S. would suffer because I would cause human costs.


Not monetarised enough?
Monetarise "national security" well first, or else the whole conscription thing lacks any revenue side!