“I've been to 70 countries, including Iraq under Saddam and Indonesia under Suharto,” says Stephen Zunes, an international-studies professor at the University of San Francisco.* “[Western Sahara] is the worst police state that I’ve ever seen.”

This political conflict, like the natural resource issues tangled into it, has remained obscure on the global front. But as other country’s domestic reserves of phosphate become more costly to extract in the coming decades, this disputed region could have more of a monopoly over phosphate than OPEC, the Organization of the Petroleum Exporting Countries, has over oil—which has major implications for the future dynamics of food and its availability in the developing world.

* * *

In the 1960s, the widespread use of synthetic fertilizer, part of the Green Revolution, allowed millions of people who would have otherwise starved to be fed by dramatically expanding the land suitable for agriculture around the world. This was driven by the Haber process, which allows atmospheric nitrogen to be converted into a form biologically available for crops. But for any increase in nitrogen in soils, life also requires a commensurate increase in phosphorus, which is mined in the form of phosphate from geologic deposits around the world. The demand for mined phosphate skyrocketed.

No matter how impressive technological advances become, a Haber-like technique for creating phosphate will never exist: There is a fixed amount in the Earth, it’s stuck in the ground, and the only way to get it is to mine it. So now there’s a controversy about how much phosphate remains in the world, and how its distribution will affect food production in the future.

In 2009, a research paper based on then-current United States Geological Survey estimates of phosphate reserves sparked fear that the world was about to enter a period of “peak phosphorus.” Its authors argued that current reserves could be depleted within a century’s time. In response, the International Fertilizer Development Center—a non-profit NGO focusing on the fertilizer industry, food security, and global hunger—released its own independent study of phosphate reserves the following year. They estimated almost four times the USGS’s amount, allaying concerns over the commodity’s imminent disappearance.

Stephen Jasinski, the USGS specialist in charge of monitoring phosphate reserves, says that almost all of this massive increase came from a reinterpretation of data provided by Morocco’s state-run mining company back in the 1980s, as well as independent studies from the same time period. The USGS now accepts these new Moroccan values as accurate. But according to Olaf Weber, a professor of sustainability management at the University of Waterloo, in Ontario, “it’s hard to figure out” exactly how much phosphate Morocco really has.