In the 1940 case Z. & F. Assets Realization Corp v. Hull, Secretary of State et al., the U.S Supreme Court dealt with a dispute over property rights and international law during World War II. The plaintiff was a corporation that had purchased assets from German companies before Germany declared war on the United States in 1941, but after President Roosevelt's proclamation of limited national emergency in September 1939 which froze all German assets within US jurisdiction under Trading With Enemy Act (TWEA). When these properties were seized by the Alien Property Custodian as enemy-owned properties under TWEA, Z&F sued to recover them arguing they were not "enemy" owned at time of seizure because it occurred prior to formal declaration of war between two countries. The court ruled against Z&F stating that for purposes of TWEA an 'enemy' included any individual or entity residing within territory occupied by nation with whom US is at war or who is doing business directly/indirectly with such nation regardless if there has been formal declaration yet; hence their purchase constituted trading with enemy making those assets liable for seizure.

The dissenting opinion in the case of Z. & F. Assets Realization Corp v. Hull, Secretary of State, et al., argued that the majority's decision was a departure from established principles of international law and an intrusion into the domain of foreign relations - traditionally managed by Congress and the President. The dissenters believed that it was not within their jurisdiction to decide on matters related to recognition or non-recognition of foreign governments, as this is typically handled by political branches rather than judicial ones. They also expressed concern about potential negative implications for future cases involving similar issues if courts were allowed to make such determinations based on policy considerations rather than legal principles.