How much was the US involved in the creation of the "Commonwealth" status in Puerto Rico?
The US was directly involved in creating the commonwealth status of Puerto Rico. This information is, most likely, available in any book or article about the history of Puerto Rico you may find.
The following is an excerpt from the Encyclopedia Britannica article:
The commonwealth
In addition to reforming the Puerto Rican economy, the PPD modified the island's political relationship with the United States. In October 1950 President Truman signed the Puerto Rico Commonwealth Bill, which enabled the island's people to establish their own constitution. Some Puerto Ricans, notably the Nationalists, opposed the new law and resorted to violence. A handful of Nationalists unsuccessfully attempted to assassinate Governor Muñoz Marín in San Juan, and Nationalist uprisings erupted in several island towns, causing 27 deaths. In November two New York-based Nationalists tried to kill Truman in Washington, D.C.
In 1951 Puerto Ricans overwhelmingly approved the commonwealth status in a referendum, and the island's constitution was proclaimed on July 25, 1952, a symbolic date because it was the 54th anniversary of the U.S. invasion of the island. The constitution reaffirmed the post of an elected governor, created a legislative branch in which minority representation was guaranteed, and set up a new judicial system based on civil liberties. Dissatisfaction continued to be expressed despite broad popular support for the autonomy of the commonwealth government and a rapidly modernizing industrial society. Nationalist violence broke out again on March 1, 1954, in Washington, when four Nationalists—three men and a woman—fired weapons from the viewing galleries of the House of Representatives, wounding five Congressmen.
Legal reviews in the courts, both insular and federal, continued to enforce the commonwealth concept. At the same time, Puerto Ricans were unable to expand the limits of their autonomy to include international diplomacy, such as playing a greater role in Caribbean affairs. Sentiment in favour of statehood grew following the admission of Alaska and Hawaii to the United States, particularly because Puerto Ricans increasingly were depending on federal aid for the unemployed, elderly, and war veterans. In addition in 1959 Puerto Ricans became highly concerned over regional security and ideology following Fidel Castro's communist revolution in Cuba, and the island absorbed a sizable influx of Cuban exiles.
Muñoz Marín stepped down in 1964 and was succeeded by his able administrative assistant Roberto Sánchez Vilella, who in November of that year became the second elected governor in the island's history. However, with the charismatic Muñoz Marín retired from the political scene, the PPD lost its firm grip on power and was fiercely opposed by pro-statehood groups. In 1968 the PPD lost control of the lower house of the legislature after a split in its ranks, and it also relinquished the governorship to Luis A. Ferré, who led the pro-statehood New Progressive Party (Partido Nuevo Progresista; PNP). Since then the PPD and PNP have alternated in power.
Puerto Rican society underwent sweeping changes during the 1960s and '70s. Agriculture lost importance, and there was rapid growth in manufacturing and in the number and size of urban and suburban settlements. In addition, cultural, political, and economic links with the United States increased as greater numbers of Puerto Ricans migrated there. The U.S. government introduced food stamps in 1974 in order to improve the diets of poorer residents, and by 1980 about three-fifths of the population was receiving the benefit.
The PPD returned to power briefly in 1973–76 under the leadership of Rafael Hernández Colón, a young protégé of Muñoz Marín. The pro-statehood PNP regained power in 1976 under the vigorous leadership of Carlos Romero Barceló, but Hernández Colón won back the governorship for the PPD in 1984 and served for two terms. In November 1992 Pedro Rossello, a medical doctor, led the pro-statehood PNP to another electoral victory, and he was reelected governor in 1996. However, a series of corruption scandals soon caused the PNP to lose support. In November 2000 the mayor of San Juan, Sila Calderón of the pro-commonwealth PPD, was elected as Puerto Rico's first woman governor.
"Puerto Rico." Encyclopædia Britannica. 2005. Encyclopædia Britannica Online. 2 Aug. 2005