A look at Puerto Rico before and after Hurricane Maria

SAN JUAN, Puerto Rico — In the days after Hurricane Maria struck Puerto Rico as the most destructive storm in the modern history of the island, a poll by a U.S. market research company added insult to injury. The Morning Consult survey found that nearly half of adults in the U.S. didn't know people born in the territory, which is about 1,200 miles southeast of Florida, are American citizens by birth.

But a lack of knowledge about Puerto Rico predates the storm.

Here is a look at the history and key issues facing the island:

THE BEGINNING

The U.S. has had a fraught relationship with the island since the late 19th century. Spain ceded it to the U.S in 1898 after the Spanish-American War, and Congress declared it an "unincorporated" territory in 1917 in an act that granted U.S. citizenship to people born in Puerto Rico. At the outset, the island functioned much like a colony, with Congress allowed to overrule any local legislation and the president given power to appoint a governor. In the late 1940s and early 1950s, the U.S. authorized the island to elect its own governor and draft a constitution. In 1952, it was re-christened the Commonwealth of Puerto Rico and a semi-autonomous relationship was codified, establishing that the U.S. has jurisdiction over national matters such as trade and foreign relations while the island's bi-cameral legislature and governor have control over local matters.

ITS STATUS

Throughout this history, the people of Puerto Rico have been split over whether they want independence, statehood or some form of the semi-autonomous relationship. The debate over the island's "status" is the central feature of its politics and divides its major political parties.

The federal government has long said that it would accept a change in the status of the Puerto Rico if the people of the island clearly supported the decision. But for decades, they have been divided between those who favor statehood and those who want to maintain the commonwealth, perhaps with some changes. A small minority continue to favor independence.

The last referendum, in 2017, strongly favored statehood but opponents questioned the validity of the vote because of low turnout.

The hitch is that any change would have to be approved by Congress. Statehood legislation, with support from Republicans and Democrats, was introduced in June but appears unlikely to gain momentum as politicians remain hesitant to take up such a thorny issue.

SEMI-AUTONOMY IN PRACTICE

Both Spanish and English are official languages on the island, but the former is more widely spoken. Puerto Ricans often refer to their island as "el pais," the Spanish word for country. Puerto Rico fields its own Olympic team and has its own cultural identity.

But Puerto Ricans can fly back and forth from the mainland without showing their U.S. passports. The more than 5 million people of Puerto Rican descent on the mainland outnumber the 3.3 million on the island. Puerto Ricans also serve in the U.S. military and many, if not most, consider themselves as American as anyone else in the country.

They do have, however, second-class political status. Residents of the island cannot cast a ballot in the U.S. presidential election, have no representatives in the Senate, and send only a non-voting member to the U.S. House of Representatives. While they don't pay U.S. personal income tax, they still must contribute for Medicare and Social Security and pay income taxes to the Puerto Rican government.

DEBT CRISIS

The U.S. federal government is now exerting an increased level of financial control over the island because of its debt crisis.

Financial turmoil is the result of massive borrowing to cover deficits over a decade-long economic recession sparked by the expiration of a manufacturing tax credit. Congress created a financial oversight board in 2016 in exchange for granting Puerto Rico a legal mechanism to restructure public debt that had spiraled to more than $70 billion.

But that proved deeply unpopular on the island, where the board's insistence on budget and benefit cuts prompted fierce protests.

HURRICANE MARIA

Hurricane Maria hit Puerto Rico as a category 4 storm on Sept. 20, 2017. It bashed the island for 12 hours, destroying the electric power grid and thousands of homes, businesses and government buildings. Puerto Ricans were also left with no power and water, no cell phone service, and a sense that the U.S. government had been ill-prepared for the disaster — which the Federal Emergency Management Agency later conceded was true.

Regardless of the relationship between the U.S. and Puerto Rico, the storm is proving to be an expensive disaster for all American taxpayers. The federal government says it has already spent more than $3 billion for recovery efforts. The government of Puerto Rico says the total cost of recovery over the next decade will be more than $100 billion, and it says it will need help from Congress to foot that bill.