Final answer:
The Supreme Court ruled that the first two national trademark laws exceeded Congress's authority under the Constitution, which led to those laws being deemed unconstitutional.
Step-by-step explanation:
The first two national trademark laws were ruled unconstitutional by the Supreme Court because they exceeded Congress's authority. This ruling was based on the distinction between interstate commerce, which Congress has the authority to regulate under the Commerce Clause of the Constitution, and manufacturing or production, which was seen as separate and mostly under state control. The significant case of United States v. E. C. Knight highlighted this reasoning by the Supreme Court, illustrating that Congress's power to regulate did not extend to the control of manufacturing, which is where trademarks would fall. Over time,Congress's regulatory authority has been further defined through various rulings, which have clarified the scope of federal power and the legislative branch’s abilities to enforce laws, negotiate treaties, and the checks it has over other branches of government.