NORTH (SAN DIEGO) COUNTY ---- Rep. Darrell Issa, a Vista Republican who has been considered in some circles a relative moderate on immigration matters, has joined a caucus of anti-illegal immigration lawmakers. Issa, R-Vista, announced last week that he had joined the Immigration Reform Caucus, a predominantly hard-line Republican group founded in 1999 by conservative members of Congress opposed to illegal immigration.His move comes at a critical time, as the U.S. Senate continues debating a controversial immigration reform bill that would pave the way to give millions of illegal immigrants a chance to become legal residents. Immigration analysts on both...