At six billion plus today, the earth’s human population will reach more than nine billion by 2050, according to estimates. If this many people consume energy at the current rate in the developed world, the planet will need more than double the amount of power it consumes today. But energy is just one issue that humankind will have to tackle to create a sustainable future. The root cause of the looming energy problem—and the key to easing environmental, economic and religious tensions while improving public health—is to address the unending, and unequal, growth of the human population. And the one proven way to reduce fertility rates is to empower young women by educating them.

High fertility rates in areas of the developing world that can least cope put tremendous pressure on freshwater and sanitation needs and fuel economic and religious tensions. In response, these countries ramp up their energy production via the only means available to them based on their resources—means that tend to either pollute the environment or contribute to global warming.

For instance, India, Somalia and Sudan have large positive birth rates. The latter two countries struggle to provide adequate food and water resources, and India increased its energy consumption by almost 50 percent between 1992 and 2001. (In contrast, Japan, France and Russia have negative birth rates, and the U.S. is slightly positive.) Indeed, a United Nations study published in August reported that Asia currently does not have the means to feed the extra 1.5 billion expected to live on that continent by 2050.

Empirical work indicating that providing schooling for women and girls will address these problems includes study after study showing that educated women have fewer children, are wealthier and are less likely to accept fundamentalist extremism. If we want a safer world, we should consider the utility of spending dollars on educating young people as an alternative to troops and weapons.

In Afghanistan and Pakistan today the Taliban have created thousands of madrassas, where children from poor families with no access to education can receive food and what passes for learning (but what is in fact quite the opposite). At the same time, they restrict access to education for women. In Gaza vulnerable young people are recruited early on to religious extremist training camps. I am not naive enough to believe that building schools and providing access to safe and secure environments for learning will alone solve our problems—we will need to create economic opportunities as well.

Moreover, in paternalistic societies where women have few rights, effecting change will be an uphill battle. For example, the government we are now supporting with troops and infrastructure in Afghanistan has recently passed legislation that food can be withheld from women who do not have sex with their husband and that women cannot go out of the house without their husband’s permission. In countries of this sort that now receive significant support from us, we need to make the empowerment of women a higher priority. As difficult and slow as the process might be, the education of women in such countries is a necessary first step to giving them the opportunity and motivation to begin to control their own destiny.

The long-term goal of reducing poverty, religious fundamentalism and overpopulation will be impossible to reach until we free women around the world from the enslavement of ignorance. More fundamental is the fact that education is a basic human right that has been systematically denied too many women for too long.