[jkimmel]

There is a set of assumptions in your argument that I believe are false.

1. Unregulated water use that allows for production of export cash crops will continue

This could easily be fixed by regulating water use properly, such that farmers have economic incentive to grow crops that are less water intensive given that CA is not water rich.

2. Market prices of current export and current import crops will hold constant regardless of growth

That's not how markets work.

If there was a sudden surge in lettuce demand, farmers in Salinas would respond to increasing prices by switching some fields currently used for export crops to lettuce, which would be consumed locally.

This is aided by point (1) above, where we could push this shift with water regulations.

On the whole -- your concerns seem best addressed by sensible regulation of water in CA, which is a long term political problem. Opposing the farm lobby is well known third rail in the CA Leg.

Nativist population control programs are not the solution to a market failure of water distribution, however they might be implemented. Opposing housing construction is even a really poor way to implement a nativist population control program.