I just finished reading Paul Bogard's The Ground Beneath Us, (I recommend it), which among other things warns us yet again about the serious issues--environmental, economic, public health, food security--associated with over-reliance on chemical and fossil-fuel intensive industrial agriculture. It's a good 40-years-later follow-up to Wendell Berry's classic Unsettling of America: Culture and Agriculture (Sierra Club Books, 1977).
It also reminded me of a much more technical and difficult book I read a few years back, Jozef Visser's Down to Earth, subtitled "A Historical and Sociological Analysis of the Rise of 'Industrial' Agriculture and the Prospects for the Re-rooting of Agriculture in the Local Farmer and Ecology. Visser, who has graduate degrees in chemistry and a long career in agricultural chemistry, returned to graduate school later in life to produce this book, which is his dissertation from the University of Waginengen (Netherlands). A pdf is available free at the link above, and I recommend it.
Down to Earth has much to say on a complex, multi-faceted topic, but one thing it says that I can't recall seeing anywhere else is that the rise of synthetic nitrogen fertilizer is not only directly linked to the munitions industry, but promoted by collusion between the munitions/agrochemical industry, government, and government-supported scientists.
In the early 20th century a couple of German scientists/engineers developed a method for converting N2 gas (a form of N not usable by plants or for making explosives) to nitrate and ammonia. It's called the Haber-Bosch process; Fritz Haber and Carl Bosch were later named the most influential chemical engineers of the 20th century. During World War II the industrial capacity for Haber-Bosch-ing skyrocketed to produce explosives. After the war, even though many of the European facilities had been destroyed, the bomb makers had lost the explosives market, and turned their attention to producing NO3 and NH4 for synthetic fertilizers. Synthetic N production and artificial (as opposed to organic) fertilizer use skyrocketed.
Even in sources focused mainly on the problems associated with synthetic N, this turn of events is reported as basically a happenstance. In agrochemical-friendly accounts, it is presented as a heroic tale. What Visser shows, however, is that the rise of synthetic N fertilizer involved collusion (conspiracy might not be too strong a word) between the chemical companies, government entities, and some academics supported by the chemical industry and government agencies. And since the U.S. had far more N-making capacity (our factories didn't get blown up in the war), much of this collusion took place in the U.S. (though the German chemical giant BASF, the first to implement the Haber-Bosch process, is also a major player).
You can't really blame the manufacturers for trying to find new markets (well, you can, but you can't really expect any other behavior). And you can't be too surprised to see government agencies helping to bail out an industry. But Visser makes a strong case that the U.S. Department of Agriculture not only favored research on synthetic fertilizers, but actually suppressed science questioning the need for them or supporting the superiority of organic N.
For all but perhaps the agrochemical industry, it is recognized that agricultural in the U.S. and other industrialized countries has an over-reliance on synthetic N fertilizer, and that in terms of plant nutrition and ecological values, organic N is superior. There is also no real disputing that the overuse of synthetic N is taking a serious toll on natural resources. And, as mentioned above, even the agrochemical industry does not dispute that the manufacture of synthetic N fertilizer evolved from the munitions industry.
What Visser makes clear, and that I wish other scholars would follow up on, is the deliberate collusion between industry and government to make it all happen. It's a lesson even more worth considering in the current environment where heads of U.S. government agencies (Scott Pruitt at EPA being the obvious example) are getting their advice from and having their agendas set by the very entities they are supposed to be overseeing.