All-Mercenary service?

[Stratiotes]

Last night I was watching Thomas Barnett's Blueprint presentation on video and it occurred to me that some sort of balance would need to be struck between protecting the homeland and projecting power. Mercenaries might be a good solution for projecting power but not necessarily desirable for defense forces - for several reasons, not least of them being fear of military coups but such a force. Many have advocated a well regulated militia for national defense - i.e., not a professional service like the national guard so much as an armed citizenry as with Switzerland. I think such a system could give us the best of both solutions. Every system is going to have flaws but this one seems to me the most cost-effective and also has the benefit of giving all Americans greater stake in our country so it should improve more involvement of the people in political movements. Seems a win-win to me.