Gov. Mark R. Warner took aim at social conservatives' favorite causes Thursday by vetoing a ban on a controversial abortion procedure and eliminating a requirement that schools display the motto ``In God We Trust.'' The new governor's efforts to squelch those measures set the stage for a showdown with the Republican-controlled General Assembly. Legislators will meet April 17 to vote on Warner's recommendations. Conservative groups were not surprised by Warner's actions. ``The governor made it very clear early on that he was not interested in social legislation of any type,'' said Victoria Cobb, director of legislative affairs for the Family...