There are other factors besides quantities of food delivered by sea. Those factors are time and availability.
In my mind, we are speaking of processed food shortage rather than bulk commodities. There is a purchasing process that requires time to first determine what is needed and then where to place orders and then purchase and wait on sea delivery.
Time is the killer. Supplies will run low before there is replenishment by sea.
My belief is that the cities will tear themselves apart with riots and looting before resupply can take place. Although Nancy and her minions control the politics, once there is a breakdown of the status quo, the cities will come apart internally. Nancy does not have the ability to provide the necessary cohesion.
It boils down to fear and insecurity. The cities cannot exist when the fear and insecurity sets in
The unknowns in my mind are at least two. What role will the military play and will the rioters be able to extend their efforts after burning the cities.
This all is a very interesting mental exercise for which there are numerous outcomes
Go back to the Detroit riots in the 60s.
Even with the 101 and 82nd within it still went on.
All over a after hour party. Thats all it took.
Adequate food would take months under a best-case scenario to arrive.
Our cities will implode and burn in weeks with no food.
Humpty Dumpty etc.