Final answer:
The Supreme Court case dealing with President Truman's Executive Order 10340 is Youngstown Sheet & Tube Co. v. Sawyer, also known as the Steel Seizure Case. It limited presidential power by ruling Truman could not seize steel mills without Congressional authorization.
Step-by-step explanation:
The Supreme Court case dealing with President Truman's Executive Order 10340 is Youngstown Sheet & Tube Co. v. Sawyer, 343 U.S. 579 (1952). This landmark case is commonly referred to as the Steel Seizure Case. It involved President Truman's attempt to prevent a strike by seizing control of the nation's steel mills during the Korean War. The U.S. Supreme Court held that the president did not have the constitutional authority to seize private property without legislative authorization. The ruling effectively revoked Truman's Executive Order 10340 and established limits on the executive powers of the President.
This case is distinct from Executive Order 9981, which was issued by Truman in 1948 to end segregation in the military. The Steel Seizure Case is a key decision in constitutional law, demonstrating the balance of power among the branches of government and confirming that the President's power is subject to limitations, particularly in areas where Congress has not granted authority.