MARK FINEMAN
 Los Angeles Times

 MANZANILLO, Cuba -- With more than 300,000 people gathered Saturday in a
 sweltering downtown plaza here, Cuban President Fidel Castro and his ruling
 inner circle delivered the nation's first official reply to the return of castaway Elián
 González: a defiant declaration of yet another ideological battle against the United
 States.

 The new official targets: U.S. immigration and trade policies toward the island.

 ``We don't care who becomes the next U.S. president,'' Castro said in a
 statement read to the rally. ``None of the aspirants inspire confidence in us. It's
 useless for them to try to win a few voters by investing unnecessary time in
 declarations and promises against Cuba. . . . Four decades of underestimation
 and humiliating failure should be enough'' for Washington to realize that ``Cuba
 was, is and will continue to be free forever.''

 Cuba's gray-bearded leader, who made Elián's return from the United States a
 personal, paternal and national crusade, did not outline a specific strategy. But in
 the two-page letter, he said neither Elián's return nor the results of the U.S.
 elections in November will ease tensions between two nations that have been
 enemies for 40 years.

 Foreign Minister Felipe Perez Roque announced that the mass Elián rallies that
 have been held in a different city around the country each Saturday since
 December would continue indefinitely, along with round-table discussions among
 senior government members and Communist Party faithful broadcast live every
 weekday afternoon. Instead of Elián, the focus will be on U.S. trade and
 immigration policies.

 Castro did not attend the rally. He was on Havana's seafront, 400 miles away,
 overseeing an in-your-face army graduation ceremony in front of the U.S.
 diplomatic mission that was televised soon after coverage of the Manzanillo
 gathering ended.

 Even Castro's younger brother, Raúl, the 73-year-old leader's official successor
 and defense minister, joined in this opening offensive.

 During a rare, 15-minute meeting with the foreign media as the masses filed out of
 the plaza here toward home, the younger Castro declared: ``Now begins the
 second stage, which also will be triumphant.''

 Citing the 1966 U.S. legislation that was Cuba's principal target of the day, Raúl
 Castro said flatly: ``The Cuban Adjustment Act has to end. Because Cuba will not
 change.''

 Jovial, self-assured and clad in a dress uniform heavy with medals, Raúl Castro,
 who is 69 and chief of the Cuban army, added with a shrug: ``What other solution
 do we have? What other solution do the Americans have? Invade us? I would not
 like to see that, because we would pay a terrible price. And they would pay as
 terrible a price as us.''

 The Cold War-era congressional act presumes that all Cubans who leave this
 Communist-run island for the U.S. are political refugees. Together with the
 38-year-old U.S. economic embargo, it was meant to help bring down Castro's
 government.

 But the law has become the cornerstone of the Clinton administration's so-called
 wet foot/dry foot immigration policy, which permits Cubans -- and only Cubans --
 who reach America's shores to remain, while those intercepted at sea are sent
 home.

 Cuba asserts -- and many U.S. law enforcement officials agree -- that the law and
 the policy are fueling a multimillion-dollar, Miami-based human smuggling trade
 that left more than 60 Cubans dead last year alone in the treacherous straits that
 separate Florida from Cuba, just 90 miles away.

 The renewed militancy of the Cuban leadership may also affect ongoing efforts in
 Washington to ease the U.S. embargo on Cuba and permit U.S. sales of food and
 medicine to the island. A struggle is going on among Republican factions -- some
 of which favor relaxing the sanctions -- and GOP congressional leaders who
 object to the change in policy.

 Democrats and the White House have complained that the Republican proposals
 do not go far enough and hinder the administration's pursuit of foreign policy
 objectives.

 Washington Post and Associated Press dispatches supplement this report.