In 1979-80 Malawi suffered a false early rains followed by a drought and then very poor rains. This was my introduction to rural development in Africa. The subsistence farmers (= nearly all farmers) had to plant a second time. It is the African equivalent of the false spring that has hit so much of eastern USA this year (and in 2012?). With a disastrous maize crop it meant by 1980-81 we had food riots until the next season's maize crop was distributed.
This happens from time to time. Farmers accept that there are good years and bad years but two or three bad years in a row can wipe them out. With a greatly increased population, especially through urbanisation, often significant soil erosion, and over-use of scarce water resources there is far less spare capacity in the food system in vulnerable parts of the world.
The question is whether unpredictability in the weather systems will continue to increase, thus threatening
food production in especially marginal parts of the world. You can see where I am going with this. It is hard not to believe that climate change will continue to significantly impact food production reliability in the world, with increased risk of societal collapse.
The world is becoming increasingly reliant for basic foodstuffs on the North American grain crops and rice production in countries like Thailand who currently can produce large surpluses. The recent disasters for soft fruit farmers in the USA and the problems for California agriculture during the recent drought would, you have thought, concentrated minds in Washington and led to increased budgets for agricultural extension staff and programmes.
It seems the opposite is happening. The world needs USA agriculture. It may have to look elsewhere.
But as Marie Antoinette did NOT say "Let them eat cake". (poor harvests and the indifference of the aristocracy to famine were a major contribution to the French Revolution).
And as Forrest Gump said "and that's all I'm going to say about that".