A-06 / Legal boundary
Seize and operate private industry solely on a broad national-defense rationale
Youngstown rejected the steel-mill seizure at issue because neither statute nor the President’s asserted constitutional powers authorized that action.
Scope and exceptions
The holding does not negate lawful purchases, DPA priorities, acquisition/condemnation under specific statutes, or other separately authorized action.
Planning implication
Do not treat mobilization strategy or an emergency declaration as a universal industrial takeover power.