Relationship of international law and municipal law — Treaties — Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on Their Destruction, 1993 — Scope and application — War crimes and acts of terrorism — United States domestic law — United States Constitution 1787 — Tenth Amendment 1791 — Federalism — Balance of powers between Federal Government and states — Police power of states — Chemical Weapons Convention Implementation Act 1998 — Section 229 — Definition of “chemical weapons” — Interpretation of defined terms — Application of express definition or use of ordinary reading — Intrusion of Federal Statute on traditional responsibilities of states — Scope of treaty power — Principle that a constitutional question will not be considered if a case can be otherwise disposed of — Clear congressional intent required for a Federal Statute to abrogate state responsibilities — Common law assault — Treaty power to be applied to matters of intercourse between nations — Whether treaty power applicable to purely domestic matters — Scope of “necessary and proper” clause — The law of the United States