There is something to be said in favor of an all-voluntary military, but on the debit side there is this: only those with 'skin in the game' — either their own or that of their loved ones — properly appreciate the costs of foreign military interventions. I say that as a conservative, not a libertarian.
There is also this to consider: In the bad old days of the draft, people of different stations – to use a good old word that will not be allowed to fall into desuetude, leastways not on my watch — were forced to associate with one another — with some good effects. It is 'broadening' to mingle and have to get along with different sorts of people. And when the veteran of foreign wars returns and takes up a profession in, say, academe, he brings with him precious hard-won experience of all sorts of people in different lands in trying circumstances. He is then more likely to exhibit the sense of a Winston Churchill as opposed to the nonsense of a Ward Churchill.
At the moment, Vladimir Putin is threatening to send his troops into the Ukraine. There are those with no skin in the game who are willing to expend American blood and treasure should the Ukraine be invaded. I humbly suggest that we secure our own borders before we worry about the borders of foreign countries. I have no skin in this game, but also no prospect of profiting from yet another foreign adventure.
Donald Trump has it right: America first!
Click on the link to learn what the slogan means.