The only truly bad plan is no plan. Everything else is personal choice and a constant balancing act between living life and enjoying today and preparing for what could happen.
But here is some interesting reading about food storage and shortages.
http://woodpilereport.com/
Unfortunately, I see a lot of truth in this report when he gets to the discussion of the Department of Homeland Security. Especially the comment from Survival Blog:
"The existing current national disaster plan calls for the requisition, by force if necessary, of all existing food and drug stocks from outlying, lightly populated, rural areas, for transport to and use in more densely populated urban areas."
Obviously, I do not have access to DHS internal documents, but I truly believe that in a major food shortage event, our already socialist-veering government will view anyone with above average food stores in their home as a hoarder and will take it upon themselves to seize and resitribute that food for the common good - theirs!
And the more government breaks down, the worse it wil be. As federal control degrades, it will occur on a local scale as lower and lower levels of politicians feel more and more empowered without oversight. I don't even consider it a stretch to imagine a scenario where local government officials declare martial law and go house to house seizing all food, weapons, ammo, medicine, and other objects of value. I am not saying it will happen, but I will not be shocked at all if we see it in out lifetimes.
Personally, I am not overly concerned about natural disasters or nuclear events. My biggest concerns are completely internal to our own country.