The Sierra Club, with over 700,000 members nationwide, is the oldest grassroots environmental organization in the United States. It sees its purpose as preservation, protection, and enhancement of the natural environment.
Article IV, Section 4. This section is called the Guarantee Clause, because by its terms the federal government makes certain guarantees to the states. One of theseâprotection from foreign invasionâcontinued Congress's prior obligation under the Articles of Confederation.
Article IV, Section 2. Our Constitutionâs Fourth Article is devoted to the relations between the states and the Union. Section 2 of that Article sets forth three Clauses, each of which concerns the movement of persons throughout the Union.