U.S. Territorial Expansion: The Constitutional Roles of Congress and the President

Research ReportCRS In FocusVersion 1

IF13163

U.S. Territorial Expansion: The Constitutional Roles of Congress and the President

Published Jan 29, 2026Updated Jan 30, 2026

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What this is

The Congressional Research Service is a nonpartisan policy and legal analysis arm of the Library of Congress. CRS reports are written for members of Congress and their staff, not the public — but they’re made available openly through Congress.gov.

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