The Santa Clarita-based nonprofit Southern Pacific Aero-Defense Alliance held its inaugural event Wednesday at College of the Canyons, with a panel discussion on California’s historical aero-defense industry and how to protect it.  Speakers and panelists spent the afternoon reiterating the importance of SPADA’s mission: to cultivate partnerships among government agencies, companies and schools to bolster Southern California’s aerospace and defense industries.  Los Angeles County Supervisor Kathryn Barger