SAN DIEGO (AP) – A centerpiece of the U.S.-Mexico deal on immigration calls for rapid expansion of a new policy that makes Central American asylum seekers wait in Mexico while their cases wind through U.S. immigration courts. It’s too early to say if the policy will achieve its goal of deterring more migrants from coming. But a growing backlog in U.S. immigration courts means waits for months, possibly years. Many say they feel unsafe in Mexico and can’t find legal advice. The policy got off to a modest start in January in San Diego and then expanded to El Paso while surviving an initial court challenge from critics. The Mexican government said last week that more than 10,000 Central Americans had been returned to Mexico so far.