Being a single mother or witnessing a gang crime could be enough for Central American illegal immigrants to get on the path to asylum under guidance the Homeland Security Department issued last week, opening up new ways for the current surge of illegal immigrants to gain a legal foothold in the U.S. The guidance, a 27-page training document from U.S. Citizenship and Immigration Services, says women who flee Central America because they fear being a single woman at the head of a household can be deemed to be part of a targeted social group, and can make a claim that...