Puerto Rico was a Spanish colony from 1493 to 1898. The United States gained sovereignty over the island in 1898 and undertook a sustained "Americanization" campaign designed to make Puerto Rico "in its sympathies, views, and attitude toward life and toward government essentially American" ( Davis 1899: 656). This campaign was waged actively for fifty years before Puerto Ricans were granted a measure of self-rule. Since then, the island has remained integrated into the legal and economic systems of the United States, which retains sovereignty over Puerto Rico.
For most federal regulatory and criminal statutes, Puerto Rico is treated as if it were a state.(General Accounting Office 213, 246-61) There are, however, some important exceptions. First, individuals and corporations in Puerto Rico pay no federal income taxes (although this permits Puerto Rico to set local taxes at significantly higher levels). (Brumbaugh 211, 214) Second, residents of Puerto Rico receive less favorable treatment than mainland residents under a number of major federal benefits programs. For citizens of Puerto Rico, federal payments under Aid to Families with Dependent Children, Medicaid, and the food-stamps program are made at lower levels and are subject to an overall cap. (S. Rep 10-11 (1990). The Supplemental Security Income Program (aid to the aged, blind, and disabled) does not apply to Puerto Rico; rather, through continuation of an earlier, similar program, benefit levels for Puerto Ricans are capped and made at lower levels than SSI payments made to eligible persons residing in the states. According to a 1990 study by the Congressional Budget Office, treating Puerto Rico as a state under these programs would have increased federal transfers to the Commonwealth by some $1.7 billion in fiscal year 1992, rising to almost $3 billion in fiscal year 1995............
