Can Puerto Rico become a State?

Answer: Yes

With that said, don't expect this to happen anytime soon. Article IV, Section Three of the United States Constitution, which outlines the relationship between each state and the federal government, mandates that only Congress, to which the island appoints a non-voting “resident commissioner”, can grant statehood, which it has not done since it admitted Hawaii in 1959.

History

After the Spanish-American war, the United States took control of Puerto Rico in 1898. In 1917, the U.S. Congress passed the Jones–Shafroth Act, popularly called the Jones Act, which granted Puerto Ricans U.S. citizenship. Three years into the first World War, this allowed roughly 20,000 of the new American citizens to be drafted into service. Despite the fact the people of Puerto Rico set up their own government in the early 1950s, their relationship with the United States Federal government did not change. Since that time the island has had four referendums regarding their desire to become a U.S. state, none of which were legally binding, and none of which gained much traction. In 1967 and 1993 Puerto Rican's voted to remain a commonwealth. On December 13, 1998 voters were given the choice between statehood, independence, free association, being a territorial commonwealth, or "none of the above". In the end, a slim majority of voters in that vote selected “none of the above” (50.3%) according to CRS Report for Congress

Latest Referendum

In 2012 Puerto Rico held another vote, this time with those advocating for statehood coming out victorious. Voters were asked two questions:

1) Whether they agreed to continue with Puerto Rico's territorial status. Basically, should we allow things to continue as they are right now.

2) To indicate the political status they preferred from three possibilities (statehood, independence, or a sovereign nation in free association with the United States)

54% voted "No" on the first question, expressing resentment against maintaining the current political status and 61.% chose statehood when answering the second question. Many people criticized the referendum because they felt it was structured in a way to generate pro-statehood results. They argued that the majority of people who voted for a change in the political status were then guided to the next step of the question which essentially said, so if you want things to change, how would you like us to do so. As noted above, over 60 percent went with the pro-statehood answer. 

Present Day

In early January of this year (2017) Ricardo Rossello "proposed several measures aimed at alleviating the crisis shortly after he was sworn in, among them a proposal to hold a referendum that would ask voters whether they prefer statehood or independence."

Resident Commissioner Jenniffer Gonzalez told The Associated Press "We are treated as second-class American citizens."

Conclusion

At the end of the day, never say never. However, until the most recent referendum in 2012 and the renewed push by Rossello and Gonzalez, becoming a state was not at the forefront of Puerto Rican's minds, let alone the minds of Congress members who seem to be preoccupied with more pressing items at the moment.  

StatehoodOld Glory