A Senate committee has concluded that while the government failed many U.S. veterans of the Gulf War, there is insufficient evidence to conclude that explosure of Iraqi nerve gas caused the illnesses reported by thousands of soldiers. The Senate Veterans Affairs Committee reached those conclusions after a yearlong study and presented them in a 310-page report Tuesday.Although highly critical of the Defense and Veterans Affairs departments, the authors of the report said they could not conclude, as other have, that nerve gas caused so-called Gulf War syndrome.