One of the biggest problems with food security is the localization of cash crops to regions of the world in which they are most economically efficient. When you really look at it, if certain agricultural capitals of the world collapsed due to sudden climate change, we could be without food for vast swaths of the world. For example, a rice shortage in 2008 sent the global markets spinning downward towards catastrophe.
Food security affects more than simple nutrition. Children nowadays are growing up without having touched loamy earth, understanding the earth from which their food grows. Government officials are putting more and more money towards imports, rather than local issues like healthcare. Communities no longer aggregate together around agricultural focal points such as the autumnal harvest or spring planting.
In my hometown, we're trying to ameliorate that. Local community gardens in a strictly urban setting have been our solution. Children are encouraged to participate, much to their delight. Communities knit together strongly, forming tribes that continue to innovate and to empower themselves.
They won't be self-sufficient on these local community gardens but these are the beginnings of something wonderful.