Quote from Altra
How do I feel about something very hypothetical?
The U.S. ended its draft in 1973 - reinstituting it would require action from Congress.
And how are we defining "the next world war"?
Basically every hospital in the US is part of (I can't remember the exact term, off the top of my head) a Federal, "Joint Service Use Agreement", where all healthcare facilities will/may be directed by FEMA and support each other, in times of mass-casualty/critical event.
So, while not legally "drafted", if you are employed in a hospital, your services may be required (by law) out of state or across the country. Generally, a, "call for volunteers", is put out, but the final legislative authority to "draft" care providers was completed after Katrina/NOLA.