WASHINGTON – A clear majority of Americans say President Donald Trump's tweets targeting four minority congresswomen were "un-American," according to a new USA TODAY/Ipsos Poll. But most Republicans say they agreed with his comments, an illustration of the nation's sharp partisan divide on issues of patriotism and race.

More than two-thirds of those aware of the controversy, 68%, call Trump's tweets offensive. Among Republicans alone, 57% say they agree with tweets that told the congresswomen to go back to the countries "from which they came," and a third "strongly" agree with them. All four lawmakers are American citizens; three were born in the USA.

That finding may help explain the reluctance of GOP leaders and most GOP members of Congress to castigate the president for tweets and comments targeting the congresswomen, liberals who are among his sharpest critics on Capitol Hill. Only four Republicans joined House Democrats on Tuesday in passing a resolution condemning Trump's comments as "racist."

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That said, the dispute could be costly for Trump among key voters in his bid for a second term. Three-fourths of the women polled call his tweets offensive. Independents, by more than 2-1, say the comments are "un-American."

Overall, 59% call the president's tweets "un-American."

The furor began Sunday morning in a string of presidential tweets aimed at freshwomen Reps. Alexandria Ocasio-Cortez of New York, Ilhan Omar of Minnesota, Ayanna Pressley of Massachuetts and Rashida Tlaib of Michigan. Trump's disparaging comments and the fierce responses from the four congresswomen and other Democrats overwhelmed attention to other pressing issues, including fundamental changes in asylum policy, the treatment of undocumented migrants at the border and a looming deadline to raise the debt ceiling and reach a budget deal.

That could presage a 2020 presidential campaign that is ignited more by cultural conflicts than by economic concerns or foreign policy issues.

The USA TODAY/Ipsos Poll of 1,005 people, taken online Monday and Tuesday, has a credibility interval of plus or minus 3.5 percentage points.

“A majority see President Trump’s tweets as un-American,” says Cliff Young, president of Ipsos Public Affairs. “However, there’s a huge partisan difference in how we interpret what’s racist in this country.”

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Two-thirds of those surveyed, 65%, say that telling minority Americans to "go back where they came from" is a racist statement. Nearly three-fourths of Democrats strongly agree with that. Republicans are inclined to agree that the comment is racist, but by a narrower margin, 45% to 34%.

Republicans are much more skeptical of charges of racism generally. Seventy percent agree that "people who call others 'racist' usually do so in bad faith." On that question, Democrats are split: 31% agree, 35% disagree.

When it comes to patriotism, an overwhelming majority – 72% of Democrats, 93% of Republicans – say they are proud to be an American. While 75% of Republicans say they are "proud of America right now," just 29% of Democrats agree on that.

There is a broad consensus among those surveyed that it is patriotic "to point out where America falls short and try to do better."

In response to a separate question, 52% of Republicans say those who criticize America are "un-American." Just 17% of Democrats say they feel that way.

The poll shows the degree to which the USA remains a nation of immigrants. Forty-one percent say that they have a parent or grandparent who immigrated from another country or that they themselves did so. There is virtually no partisan difference on that question: 45% of Democrats, 43% of Republicans.