A meeting of civic, business and government leaders from both sides of the border yesterday was intended to foster economic integration of San Diego County and Baja California. But participants in the Forum Fronterizo soon found themselves addressing a very different topic: illegal immigration and the proposal for a new border fence. “Building a wall is an anachronism,” said Jessie J. Knight Jr., president and chief executive of the San Diego Regional Chamber of Commerce. “Nobody can possibly believe that this is the solution. . . . There are other ways to ensure security.” The Forum Fronterizo, sponsored by the...