Because war is a horrendous fact of life and when it happens it’s all hands on deck for survival’s sake. Whether or not draftees feel like going to war is immaterial, that’s the point.
I don’t disagree that war is a horrendous fact of life, but survival is not at stake in all wars and we’ve shown that it will be used unnecessarily and disproportionately against the poor and other disadvantaged groups.
It’s sometimes even used as an alternative to prison, which doesn’t really “help” your cause. If the people doing the fighting don’t want to be there, and aren’t wanted there, that could ultimately do more harm than good and work against the point of the draft altogether.
Then after the war, the drafted troops who return will have PTSD and other health problems being stuffed into a healthcare system that isn’t properly funded and will already be strained. And then there are the ones who never return, putting additional burdens on families who have to figure out where to go from there.
I think the point could be argued that it’s used as a short term fix that ultimately creates more problems than it solves and it’s used without thinking of the long term repercussions. It’s also not used responsibly (I know that’s subjective) so it just becomes a card to play when someone has a vendetta that’s not going well and the sunk cost fallacy becomes the ultimate justification.
If the US genuinely gets to the point where we need to draft people, we’re already fucked. We were able to sustain two major wars while maintaining a presence all around the world in military bases and various other smaller operations and still giving troops time off between deployments.