United States2 or U.S.2 (second meaning)
The "federal zone" is a separate nation-state over which the Congress has exclusive legislative jurisdiction, not subject to constitutional limitations. This zone is called "The United States," just like the collection of nation-states over which Congress has only constitutionally-limited legislative jurisdiction are called "The United States." Keep this in mind next time you're reading congressional legislation or the U.S. Federal Law Codes, where this crucial distinction is made through language construction and definitions rather than any kind of obvious labeling scheme. dimitriThe authority to exercise exclusive legislative jurisdiction over the District of Columbia and the federal enclaves originates in Article 1, Section 8, Clause 17 (1:8:17) of the U.S. Constitution. By virtue of the exclusive authority that is vested in Congress by this clause, Congress shall have the power:To exercise exclusive legislation in all cases whatsoever, over such district (not exceeding ten square miles) as may, by cession of particular States, and the acceptance of Congress, become the seat of government of the United States, and to exercise like authority over all places purchased by the consent of the legislature of the state in which the same shall be, for the erection of forts, magazines, arsenals, dock yards, and other needful buildings;The power of Congress to exercise exclusive legislative authority over its territories and possessions, as distinct from the District of Columbia and the federal enclaves, is given by a different authority in the U.S. Constitution. This authority is Article 4, Section 3, Clause 2 (4:3:2), as follows:The Congress shall have Power to dispose of and make all needed Rules and Regulations respecting the Territory or other Property belonging to the United States2;Within these areas, it is essential to understand that the Congress is not subject to the same constitutional limitations which restrict its power in the areas of land over which the 50 States exercise their respective sovereign authorities:...[T]he United States2 may acquire territory by conquest or by treaty, and may govern it through the exercise of the power of Congress conferred by Section 3 of Article IV of the Constitution .... In exercising this power, Congress is not subject to the same constitutional limitations, as when it is legislating for the United States3. ... And in general the guaranties [sic] of the Constitution, save as they are limitations upon the exercise of executive and legislative power when exerted for or over our insular possessions, extend to them only as Congress, in the exercise of its legislative power over territory belonging to the United States2, has made those guaranties [sic] applicable.
Hooven & Allison Co. vs Evatt, 324 U.S. 652 (1945)In other words, the guarantees of the Constitution extend to the federal zone only as Congress makes those guarantees applicable, either to the territory or to the citizens of that zone, or both. Remember, this is the same Hooven case which officially defined three separate and distinct meanings of the term "United States". The Supreme Court ruled that this case would be the last time it would address official definitions of the term "United States". Therefore, the Hooven case must be judicially noticed by the entire American legal community.
From The Federal Zone, Chapter 4: The Three United States
Glossary: United States