The chairman of the Ford Motor Company, William Clay Ford Jr., wanted a meeting. Calling just hours after the terrorist attack on Sept. 11 and outrunning eruptions of anti-Arab hate that would soon bubble up across the country, Mr. Ford wanted to talk at once with local Arab-American leaders. He wanted to know what he and his company could do to ease their fears. Indeed, senior people at the company shared those fears. Jacques A. Nasser, the chief executive of Ford, was born in Lebanon.

"What that phone call meant is that Arab-Americans are part of the fabric of the Detroit area, in fact, part of the fabric of the entire country," said Mr. Ahmed, executive director of Access, an organization that provides social services here for a large and growing community of Arab immigrants.

As for incidents of brown-skinned people being kicked off commercial airplanes, assaults and three murders in Arizona, Texas and California ・all of which appear to be part of a backlash against Arab-Americans and other people who might look like them ・Mr. Ahmed shook his head in disgust during an interview here this week.

"I feel sorry for people who don't understand yet what America has become," he said, referring to Americans who scapegoat their countrymen based on skin color or religion. "For them, I'm afraid, life is going to be miserable."

The country's national political and business leadership does understand, Mr. Ahmed and several other prominent Arab- Americans said. In the decade since the Persian Gulf war, something fundamental has changed, they said, in official attitudes toward Arab-born residents and Islam.

Demands for ethnic and religious tolerance, especially from President Bush in his nationally televised speech to Congress and his visit to a Washington mosque, are driven by necessity, as well as by a sense of fair play. Arab- Americans are important voting blocs in Michigan, Illinois, New Jersey, New York and California. As Mr. Nasser's position at Ford suggests, they are also integrated into the country's power structure.

Statements by President Bush and other leaders appear to be having a substantial effect on moderating the behavior of Americans, said Ziad Asali, president of the American- Arab Anti-Discrimination Committee, the largest Arab-American group in the country.

"The tone of the country's leader ・all officials, at all levels, including law enforcement ・is exactly the right tone and it is carrying clout with the public," Dr. Asali said. "In the past few days since the reports of race-motivated murders, we have heard substantially fewer complaints from our constituents. We are receiving much, much less hate mail. We are quite gratified."

Dr. Asali said admonitions from Mr. Bush and other national and state leaders had helped isolate and shame those who might attack Arab- Americans. "It has cast the extremists as just that ・extremists," Dr. Asali said.

A look at census figures, civil rights laws and standards of political discourse shows how complicated ・and illegal, and politically unacceptable ・it has become to single out enemies based merely on dark skin, religious belief or a turban.

In large measure, several demographers said, it is because the country has in the past two decades soaked up the largest waves of nonwhite immigration in its history. Of the country's 30 million foreign-born residents, only one in four is white.

Arab-Americans and other residents who bear a skin-deep resemblance to them are increasingly part of the nation's power structure.

After the 1941 attack on Pearl Harbor, President Franklin Delano Roosevelt ordered more than 100,000 Japanese-Americans into camps surrounded by barbed-wire fences.

About 99 percent of the country's foreign-born residents were white in 1940, compared with just 25 percent now. Immigrants then were concentrated in a few major cities in the East and upper Midwest.

In the 2000 census, about one million Americans reported that they were of Arab descent and 10 million identified themselves as Asian-Americans.

"The demographics of America show that Arab-Americans, as well as East Indians and other Muslims, are not going away," said Mr. Ahmed, who lives in this Detroit suburb where a quarter of the population is Arab-American.

That percentage is rising fast because of new immigrants from countries like Iraq and Yemen. They tend to have large families. The inexorable power of demographics has bulldozed new boundaries for political discourse in the Detroit area and in other cities where Arab-Americans live and vote.

Nabeel Abraham, an anthropologist who is co-author of "Arab Detroit," said that since the gulf war, during a decade of accelerated immigration from the Middle East and Asia, he had observed a "phenomenal" improvement in attitudes toward Arab-Americans in the news media and among elected officials.

"It is like night and day," he said. "In the 1980's, when the Reagan administration said it was waging war on terrorists like Libya's Qaddafi, almost all of the government and officialdom was indifferent to Arab- Americans in this country. Now Bush is going to a mosque. The tone is being set on top and it is making a difference."