You're correct that product manufacturing is mostly Asian, but design is still mostly in Silicon Valley.  IMO (I work in this industry) that's likely to stay true.  
National Semiconductor is still one of (South)Portland, Maine's link to the Northeast's bid for Tech mfg.  Don't know what gets produced here.

I don't think tech demand will go down. Ability to MEET that demand might, though. (Don't forget credit.. cause the consumer won't, and demand for that will be WAY up..)  It will be tech solutions that will allow a consumer to find more Energy-Saving solutions to rising rates.  Microwave Ovens, (the most energy efficient way to heat food, next to Solar) Laptops and other low-power computing and entertainment solutions, like the above-mentioned Ipods.. phones, radios, LED and CF lighting.. Inverters and charge controllers, electric transp.

If we'e talking about conditions bad enough that local food production is an advantage then we're talking about a recession that will eliminate tech demand.  Nobody's going to be designing new chips or cell phones for multibillion fab shops that will never get built, because business investment will go to zero.  Consumer spending will consist of average people trying to keep up with 10-15% energy inflation costs every year.

I mean, in this case we're talking about remotely grown food being too expensive for the average person but computer sales are going to stay strong?

This isn't to confuse the latest dingle from Sharper Image with the useful technology that is more or less ubiquitous in our lives these days.  There are semiconductors involved in items all through our lives now, and we will continue to use and demand them, because they do work in ways that basically nothing else will.  The basic idea of a Transistor is simply an energy management tool.  It's a valve, a switch, a floodgate that can, with VERY little power applied to it, manage a much greater source of electrical power, making very smart and efficient use of a limited amount of electricity as required.  So I would argue that these will continue to be tools that we keep in our kits, keep manufacturing, keep finding new uses for, probably mostly BECAUSE our needs have become more stringent.  Depending on how 'Mad Max' things are to become here and there, the mass of circuit-boards that languish in landfills and basements might become the new 'Spanish Galleons' that treasure hunters will scrounge out for their precious components, but this range of tools, from electronics to materials sciences is what we have instead of claws and fangs for survival, and we won't let go of them lightly, just because we also have some sod under our fingernails.  

 Our Farming won't be some PBS special on "Colonial House", either.  We're not just jumping back to 1613 and tossing out Radios, Electric Motors and Generators, Fiberglass, Pneumatics, Chemistry, Flight, Calculators... or Literacy..