I don’t know if adding MCRD’s 400 acres to the existing 600 would help. The problem is that they need another runway. Lindbergh is the busiest single runway airport in the country. I think the goal was to find a site that had 3,000 acres. That’s 3 times as big as the current airport plus MCRD.
I personally would support Miramar. Centrally located, plenty of room. Until the military gives us a better idea of why we can’t have it, that will stay my opionin. I don’t see national defense as a problem. The base would still remain open, they’d just have a commercial airport next door. How would that impede national defense? Training flights could go on as they do now. And if there ever was an attack or some sort of problem, obviously the base would take precedent. Besides commercial airports close down anyway (at least they did during and after 9/11).