Butler is the quintessential city of immigrants. It always has been, and still is.

Lyndora native Abie Abraham, namesake of the new VA Butler Health Care in Center Township, and survivor of the Bataan Death March during World War II, wrote fondly in his memoirs about the diversity of the working-class people he encountered while growing up here. Immigrant laborers from distant lands, flung together as neighbors, often relying on grandchildren to translate — yet they all learned to love and respect each other, and to celebrate their diversity.

Fact is, those grandchildren — the generation of Abies — managed to win that Great War.

Thursday’s front-page story about Puerto Ricans living in Butler, worried about loved ones affected by Hurricane Maria, demonstrates that the spirit of diversity endures here. There are obvious changes in the cast and the narrative, but the story is essentially the same now as it was when Abraham was born in 1903.

However, there are some differences, and the differences are noteworthy.

For one thing, Puerto Rico is a U.S. territory. Its 3.5 million inhabitants are U.S. citizens, free to travel and relocate anywhere in the country. They vote. They pay federal income tax.

Here’s another thing: Even before Maria ravaged much of island’s infrastructure, an alarming number of residents were leaving. Puerto Rico’s population has fallen by 12 percent, 446,000 people, between 2004 and 2016, according to the Pew Research Center.

Analysts point to a financial crisis rooted in the phase-out of tax breaks that Congress had offered manufacturers for locating in Puerto Rico. The breaks, which let Puerto Rican subsidiaries of U.S. companies send earnings back to the mainland without paying federal corporate taxes, were phased out gradually over 10 years from 1996 to 2006. Manufacturers responded by closing plants. An estimated 100,000 manufacturing jobs were lost.

Two years later, the market collapse of 2008 sparked the Great Recession, a second crippling blow for Puerto Rico.

Analysts anticipate a flood of residents leaving the territory in coming days. “We’re talking about 100,000 to 200,00 people,” predicts Edwin Meléndez, director of the Center for Puerto Rican Studies at the City University of New York.

A population shift of that magnitude has political, social and economic ramifications. In 1980, the Mariel boatlift deposited 125,000 Cubans in Florida, permanently altering the state’s culture and politics; the Maria migration could be much larger.

A few are likely to relocate here. We should welcome our new neighbors, not only because they are American citizens — which indeed they are. We should not forget where we came from. Nearly all of us are descended from outsiders who moved here looking for a better life.

And that kid whose family just moved in next door might grow up to be the next Abie Abraham.