PROMPTED by California's anti-immigrant law and friction from closer ties with the United States, Mexico is preparing to allow its citizens abroad to acquire dual ''nationality'' as a way to better promote and protect their interests.
Under a proposal now before the Mexican Congress, the Constitution would be changed to allow its nationals who become citizens of another country to retain Mexican nationality -- something the government has firmly rejected in the past.
''This is an empowerment issue whose time has come,'' says Jorge Bustamante, president of the College of the Northern Border in Tijuana and a leading Mexican migration expert.
He predicts that some 2 million Mexicans living in the US who have been reluctant to give up their Mexican nationality would be encouraged by the chance to become US citizens -- and thus gain voting and other rights.
Other experts say that up to 4 million Mexicans residing in the US would take advantage of the change.
On Tuesday, the Mexican Congress formed a four-party commission, including the ruling Revolutionary Institutional Party (PRI), to study the double-nationality amendment. Since the idea is supported by the PRI, there is little doubt the change will be enacted.
''This is a way to give Mexicans living abroad the same voting, health, and other rights enjoyed by other citizens in that country,'' says Alejandro Carrillo, the PRI's international affairs director.
If Mexico is willing now to enact a sensitive constitutional change that alters the country's concept of sovereignty over its own citizens, it is largely the result of Proposition 187. The California proposition, which passed overwhelmingly last November, denies educational, health, and other services to illegal immigrants and their children. It was widely interpreted here as a racist, anti-Mexico law, perpetrated against defenseless migrants. The government quickly saw that its protests had no effect across the border.
''This is a drastic change for the [Mexican] government, but it's the result of Mexico bashing,'' says Mr. Bustamante. ''There is deep frustration over [California Gov.] Pete Wilson, Sen. [Alfonse] D'Amato, and how Mexico is increasingly talked about and treated in the US.''
GOVERNOR Wilson rode to reelection in November on an anti-immigrant wave, while more recently New York's Senator D'Amato has loosed fiery attacks on what he's called ''starving Mexico'' in his attempts to halt further disbursement of US money in the Mexico financial-rescue plan.
Historically, Mexicans have been among the most reluctant immigrants to the US to give up their nationality of birth. ''Ours is a chauvinist country, where you were brought up with the idea that you are Mexican always, that you could never be something else,'' says Francisco Javier Guerrero, a researcher at the Center for Chicano and Border Studies here.
But now with Mexico and the US becoming more interdependent economically, with an estimated 1 in 5 Mexicans having a close relative in the US, and with millions of Mexicans in the US running the risk of losing basic services, the resistance to double nationality is ebbing. ''This is pragmatism at work,'' says Mr. Guerrero.
Economic factors also have played a role. ''They don't want to lose the land they left behind,'' says Mr. Carrillo.
SOME Mexican analysts with contacts on both sides of the border have supported the double nationality concept for more than a decade. The left-wing Revolutionary Democratic Party, which grew out of a split with the PRI and has close ties to California Chicanos, has also promoted the idea for years.
But not until the Mexican consul in Los Angeles, Jose Angel Pescador Osuna, began pressing the Mexican government following the Proposition 187 vote in November did the idea begin moving.
Bustamante, who is also a professor of sociology at Indiana's Notre Dame University, says the impact of the more than 2 million Mexicans who could take advantage of the law would be greater than their numbers suggest because they are geographically concentrated.
''About two-thirds are in California, 20 percent are in Texas, and Mexican-Americans tend to vote Democratic,'' he says. Yet he admits that the Mexican desire to influence US politics, which he says is one of the incentives behind the constitutional change, remains ''a gamble.''
The Democratic lock on Hispanic voters has loosened in recent elections. A greater cause of consternation for Mexico might be a recent poll in Texas, which showed a majority of Mexican-Americans there supporting the concept of Proposition 187.