Chicken/Egg conundrum. LA's low-density sprawl exists for three (maybe four/five) reasons: Geological (quake shake = low rise makes sense), availability of land

Chicken/Egg conundrum. LA's low-density sprawl exists for three (maybe four/five) reasons: Geological (quake shake = low rise makes sense), availability of land, and lack of suitable transport infrastructure. (Possible forth reason is the overall history of the place, maybe we're just at the apex of that time when various disparate towns come together to form the city and we're not quite done with that process yet). I guess there's a tenuous fifth reason which is LA's road infrastructure is at the extreme end of feasibility, including but not limited to the inhabitant's seemingly infinite patience for rush-hour gridlock. If you believe the earthquake risk, land area, and roading are reasons enough that urban intensification has not occurred, then adding (more) rail doesn't really make sense. On the other hand, you could regard lack of rail as being the only thing holding back urban intensification, and the lack of it being the very reason for LA's current sprawl. Providing you don't regard the other factors as hard limiters, of course. So in one school of thought: there's nothing really stopping the rest of LA intensifying in the same way as downtown (and the airport area), other than a lack of suitable transport infrastructure to facilitate it. So assuming intensification is a thing you want, there is the argument to invest and deploy the trains; in a few years you should see a great intensification of the new corridor areas of LA where it previously didn't make sense. Personally, I'm not on board with the idea - The quake hazard alone is reason enough to keep things flat and wide. I might be somewhat conservative in that regard of course - Continually echoing in my mind is that statement from 'the really big one' article a few years back that said 'everything west of Interstate 5 will be toast', as far as how I judge LA's realism on earthquake risk.