Authorities are trying to determine why two men in a pickup truck ran a checkpoint at Davis-Monthan Air Force Base this morning, crashing into a traffic barrier aimed at stopping unauthorized base entry. Terrorism is not thought to be a motive at this point, but military officials and civilian police hope to learn what prompted the pair to speed past the control gate at Swan and Golf Links roads without stopping for required identification checks. Both occupants of the 1999 Dodge truck were taken to University Medical Center with serious injuries. The men were not carrying identification and were unconscious...