On Puerto Rico's southwestern corner, the sleepy seaside town of Guanica is where, nearly 120 years ago, the U.S. relationship with the island began during the Spanish-American War. The town's museum director, Francisco Rodriguez, takes visitors to the town's waterfront where the invasion began. In Spanish he says, "This is Guanica Bay, where the American troops commanded by General Nelson Miles landed on July 25, 1898." At the site, a stone marker engraved by the 3rd Battalion of the U.S. Army commemorates the invasion.

Nearly 19 years after the invasion, President Wilson signed the Jones-Shafroth Act, granting citizenship to people born on the island. But it's a limited form of citizenship. The law puts Puerto Rico under federal control but doesn't allow the island voting representation in Congress. Residents also can't vote for president. That law started a debate that continues today over what exactly the island's relationship with the U.S. should be. And now in Puerto Rico, there's a new push to fix what many see it as a deeply-flawed relationship.

For decades, Puerto Rico's three political parties have pushed for three basic positions: statehood, independence or the status quo or commonwealth status. But nearly all Puerto Ricans agree on one thing, says Gov. Ricardo Rossello.

"Regardless of what ideological twist people may have, about 90 to 95 percent of our population really values our citizenship, so it's of utmost importance," he says.

One reason Puerto Ricans treasure U.S. citizenship is that it allows them to travel freely to the mainland. Over the last decade, while the island was mired in a recession, hundreds of thousands of Puerto Ricans migrated to Florida, New York, Texas and other states.

Rossello is with the New Progressive Party, which advocates statehood. He says Puerto Rico's strength is its status as part of the United States. "The bad side of it is that we are not a full part of the United States," he says. "We're a territory or a colonial territory. We're aiming to change that and of course, from my perspective, I'd want Puerto Rico to become the 51st state of the nation."

Today the question of Puerto Rico's status is one debated on the campaign trail. But over the last century, the push for Puerto Rican independence several times led to violence, including an attempt to assassinate President Truman in 1950 and then, four years later, an attack on Congress, in which five lawmakers were wounded.

Since then, support for outright independence has declined on the island as the Puerto Rican population has grown on the U.S. mainland. Support also has declined, at least among elected officials, for maintaining the status quo. Last year, a Supreme Court decision undercut the island's long-standing claims of autonomy. Around the same time, struggling with more than $70 billion in public debt, Puerto Rico was forced to hand over financial control to an oversight board established by Congress.

Manuel Natal, who serves in Puerto Rico's House of Representatives with the party that supports the current commonwealth status, believes change is needed, but worries statehood would force Puerto Ricans to give up things they've long treasured.

"We can talk about language, our cultural identity," he says. "We can give plenty of examples of things that are important to the people of Puerto Rico on day-to-day, and we are not sure how we would come about if statehood was a reality."

Francisco Rodriguez, is the museum director in Guanica. Most people there support statehood because of the town's historical connection to the U.S.

Natal supports a political status called free association. That would enable Puerto Rico to maintain its close relationship with the U.S. while allowing the island autonomy to make its own trade deals.

He thinks the U.S. Congress might find free association more acceptable than statehood, in part because statehood would grant Puerto Rico more power in Washington — two U.S. senators and as many as five House members, numbers that could affect Republican control in Congress. And, Natal says, with President Trump's pledge to build a wall on the U.S. border, Washington is unlikely to welcome a state where Spanish is the first language.

"I'm a Puerto Rican citizen, a U.S. citizen with a thick accent," he says. "I understand what's going on there and I know that statehood is not a possibility."

In June, Puerto Ricans will go to the polls to choose between two options: statehood or independence/free association.

In Guanica, Rodriguez says most support statehood, in part because of the town's historical connection to the U.S. "Puerto Rico lacks resources, but that's not the fault of the U.S.," he says.

But it's a town with a mixed legacy. Every year, Rodriguez says, members of the island's independence movement come to Guanica to protest. It's a place that's both a source of pride, and for many, a symbol of colonialism and a century-long dysfunctional relationship with the U.S.

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