MULHOUSE, FRANCE — A RESTAURANT owner in downtown Mulhouse breaks away from his grill to make a point about his city in northeastern France.
''Look out at that street,'' he says. ''I see drugs, prostitution, 25-year-olds driving cars that cost 35,000 francs [$7,320]. How do they get the money? They don't talk like us. If you ask them to name French authors, they can't give you any. I can't even hire North Africans. I serve Alsatian food here. [Muslims] don't eat pork. What am I supposed to do? Serve shish-kebab and Coca-Cola? I believe in modernity, but enough is enough.''
In the past, such views might have been dismissed by the nation's leading political parties as simply racist or as an isolated response to urban blight.
But even here in Alsace, one of the most prosperous regions in France, the conviction is growing that the country has too many foreigners and that borders should be closed. The outcome of this debate over immigrants could show whether national leaders can restore public confidence in European union and open borders.
Alsace has had a long tradition of openness to outsiders. Some 60,000 Alsatians cross the border every day to work in Switzerland or Germany. More than a third of its industrial jobs are created by foreign investors, and 97 percent of the region's youths speak three languages. In 1992, 65 percent of Alsatians - the highest percentage in France - endorsed the Maastricht Treaty, which laid out a blueprint for deeper European integration.
Yet this year, the region's voters handed presidential candidate Jean-Marie Le Pen, leader of the extreme right-wing National Front party, his highest score in France. One in 4 voters in Alsace backed Mr. Le Pen's calls to close French borders and expel immigrants. Regional National Front candidates also made gains in June's local elections.
''We're very concerned [about the National Front vote] because it goes against what we've always said about the region, that it's open to the exterior,'' says Sabine Coquelet, a spokeswoman for the Alsace Development Agency.
French observers see the Alsace vote as significant. ''All the other trends - such as the growth of National Front voters among working-class voters and the unemployed - were known before,'' says Nonna Mayor, research director with the Paris-based Center for the Study of French Political Life. ''What's new in this year's vote is the party's support in Alsace.''
Regional activists wondered at the origins of a protest vote in small, quiet towns that seem to have nothing much to protest. ''Is there a single rational reason to choose the theses of Le Pen at 46.25 percent in a rural community with 96 voters?,'' wrote Jean-Paul Gutfreund, secretary-general of the CFDT trade union in a letter to the Regional Council after the presidential vote.
Catherine Trautmann, Socialist mayor of Strasbourg, the region's largest city, says the only way to fight the National Front is by refusing to legitimize the party. She denied Le Pen a municipal hall for a rally during his presidential campaign despite court sanctions.
''Xenophobia is condemned by French law,'' she said in an interview. ''Elected officials should refuse to take up those themes.''
''The views of the extreme right have become commonplace,'' she adds. ''Many politicians now pick up National Front themes, such as immigration or security, and that contributes to a sense that they are a legitimate party.''
But in the industrial city of Mulhouse, Socialist officials and community volunteers say that it's not enough to attempt to ''demonize'' the National Front, which won more than a third of the vote here in June's local elections. They say that addressing the issues is the only way to ease public fears.
''We can't just say that the National Front is racist,'' says Dominique Picard, a local teacher who founded an association to promote racial understanding.
''Many parents spent all their savings on their kids and the kids still don't have a job. They see violence on television programs from the United States and they're afraid that will come here. The problem is not immigrants, it's the economy.''
Ms. Picard looks out at multiracial groups of young people chatting in Mulhouse's historic central square. ''You know, many old people are now afraid to come here because they are anxious about foreigners,'' she adds.
Immigrants and their children, invited here by owners of the city's textile and later automobile industries, make up 25 percent of the population of Mulhouse. Unemployment, while only 7 percent in the region, is 14.5 percent in the city.
''Because we have more unemployment, we have more National Front votes,'' says Socialist city official Robert Cahn. ''The unemployed say, 'If there were fewer immigrants, I'd have work.' In little villages, voters fear that what's happening in Mulhouse will come to them. It's a vote of precaution, a call for more order and discipline.''
National Front activists in Alsace are targeting the sagging economy in their platforms. In Obernai, a town at foot of the Vosges Mountains, Le Pen was the No. 1 choice here in this spring's presidential elections. Isabelle Chambon, who led the National Front's bid to try to win City Hall a month later, insists that the National Front is not out to attack immigrants.
''We are attacking French politicians who have resigned their duty to defend the nation,'' she says. ''Our main point is that France has a big past and we want to remain an important country. But we're destroying our industries, shipbuilding, shoes, textiles, steel.... The Japanese protect their industry, and so should we.''
Meeting in Obernai after the election, several National Front members feared that the problems of larger cities may be on the way. ''I saw crime in the suburbs of Strasbourg when I was a student there,'' says Sandrine Rudnik, a chemical engineer. ''It could happen here.''
''For a while, the other parties didn't want to talk about us,'' says the Front's Ms. Chambon. ''Now they're saying maybe they did it wrong and perhaps we need to look at the issues.''