Canada would like to talk to you about car parts and being a preferential region for that as well (Ontario, think Windsor i.e. right across from Detroit - not that Detroit's car manufacturing is going strong or anything like that but still).
Growing food in California should be re-thought if you ask me, given the prolonged drought conditions. At some point shipping water to California just doesn't make sense any longer. Instead of shipping the water to California, grow the food where the water is, even if the yields aren't as high. Like you said, a single crop failure in California can wipe out near 100% of the US' food production for certain fruits and vegetables or at least a very very sizable portion of it.