I was just wondering how many roads one would have to block and for how long to starve a major city.
Not too many or for too long, I don’t think. The stores use the “just in time” model and run out of things quickly. This is why people are concerned about disruptions caused by natural disasters, EMP attacks and other terrorism, epidemics, etc.
No need to block the roads, just shut down the EBT system and it will happen organically from within.