The divisions were deeper when it came to politics. While 66 percent of Republicans surveyed said they associated the flag with their own party, only 34 percent of Democrats said the same.
At its 1777 inception, the flag’s very design signified unity, the joining of the 13 colonies, said John R. Vile, a professor of political science and a dean at Middle Tennessee State University.
Politicizing the American flag is thus a perversion of its original intent, according to Professor Vile, who is also the author of “The American Flag: An Encyclopedia of the Stars and Stripes In U.S. History, Culture and Law.” He added, “We can’t allow that to happen.”
“It’s E Pluribus Unum — from many, one,” he said, citing the Latin motto on the Great Seal of the United States. “If the pluribus overwhelms the unum, then what do we have left?”
The sentiment of some conservatives is that a line was drawn when Colin Kaepernick, the former National Football League quarterback, set off a national movement protesting the shootings of Black men by police by taking a knee during the anthem in 2016. His kneeling protest, Mr. Kaepernick has said, still demonstrated respect for the flag, but others saw him as hijacking the flag for political purposes.
Maryneily Rodriguez, 33, said she believed that Mr. Trump’s most fervent supporters had done the same. Ms. Rodriguez, who was visiting Greenport with her fiancé during the Fourth of July weekend, said that she once regularly flew the flag at her home in Freeport, about 80 miles west on Long Island, taking it down only in winter for safekeeping. But about three years ago when spring came, Ms. Rodriguez, who is Black and a Democrat, left the flag in storage. It hasn’t come out since.
“It felt like it didn’t belong to me anymore,” she said.
John Hocker, a Republican who said he sometimes votes Democratic, also said he felt the flag had lost its meaning of unity. Instead of saluting the same flag as one people, he said, too many Americans were modifying it to become emblems of their own identities or belief systems, for instance with rainbow stripes, a symbol of gay pride, or blue stripes to show solidarity with the police.