The global war on drugs is killing Mexico: A new study found that violence from the drug war caused Mexico's life expectancy to stagnate — and, in men's cases, drop — after six decades of increases.

The study, published in Health Affairs, found that male life expectancy in Mexico fell by about seven months between 2000 and 2010, as the nation's homicide rate rose from about 9.5 per 100,000 people to 22 per 100,000 people. Female life expectancy didn't decline, but gains slowed. (Men are generally more likely to be killed in drug-related violence.) This was a sharp shift from the steady gains the country had made for about six decades, the study found.

Breaking down the numbers further, life expectancy increased in 30 of 31 Mexican states between 2000 and 2005, but decreased in all states between 2005 and 2010.

The timing is no coincidence: Mexico stepped up its drug war in 2006, bringing a new wave of homicides as Mexican officials and drug cartels clashed in horrific violence that killed soldiers, police, drug cartel members, and civilians.

The researchers noted, "The mortality rate for males ages 20–39 in Chihuahua in the period 2005–10 reached unprecedented levels: It was about 3.1 times higher than the mortality rate of US troops in Iraq between March 2003 and November 2006."

The life expectancy stagnation came despite sweeping health care reforms passed in Mexico in 2004, before the country stepped up its war on drugs. According to the study, the program, Seguro Popular de Salud, improved distribution of health resources and boosted coverage of the uninsured. But any gains that program produced weren't enough to overcome the drops in life expectancy caused by more homicides.

What's worse, researchers noted that homicide rates are much higher in other Latin American countries, many of which have been hit particularly hard by the drug war in the past few years, such as Honduras and El Salvador. So Mexico isn't even the worst possible scenario.

The findings are troubling. But they're also a direct result of what the US and other developed nations effectively expect developing countries to deal with in the drug war.

The drug war causes horrific violence around the world

What if I told you that the US could sacrifice tens of thousands of American lives to potentially save a few thousand lives in Canada and other developed nations? Would it seem like a good trade-off to you?

Most Americans, I'd guess, would not accept this trade-off. But that's what developed countries, including the US, essentially expect from Mexico and other developing countries embroiled in drug violence as a result of the war on drugs. In a 2014 paper, economists Daniel Mejia and Pascual Restrepo explained:

Suppose for a moment that all cocaine consumption in the US disappears and goes to Canada. Would the US authorities be willing to confront drug trafficking networks at the cost of seeing the homicide rate in cities such as Seattle go up from its current level of about five homicides per 100,000 individuals to a level close to 150 in order to prevent cocaine shipments from reaching Vancouver? If your answer to this question is 'perhaps not,' well… this is exactly what Colombia, Mexico and other Latin American countries have been doing over the last 20 years: implementing supply-reduction policies so that drugs don't reach consumer countries at the cost of very pronounced cycles of violence and political corruption, with the consequent losses of legitimacy of state institutions.

The way the drug war works is that developing nations, such as Colombia and Mexico, act as manufacturing and transshipment countries for drugs, while the US and other wealthy countries make up the great majority of demand for these illicit substances. So criminal groups will produce cocaine in Colombia and ship it to Mexico, and the drug is smuggled into the US from there.

It's not that Colombians or Mexicans don't use drugs, but demand in the US — where people are wealthier and can thus better afford an expensive drug habit — is much higher. This is obvious in national drug surveys: They show that in 2011, about 1.5 percent of Mexicans ages 12 to 65 used illicit drugs in the previous year, while about 8.7 percent of all Americans 12 and older did in the previous month. (The age and timespan differences are due to differing methodologies in national surveys, but they nonetheless show that way more Americans than Mexicans use drugs.)

In theory, the Mexican government and those in other developing nations should be able to stop drug violence within their borders, and crack down on drug trafficking groups to suppress crime just as well as the US and other developed nations have.

But Mexico and other developing countries don't have the incredibly powerful political, economic, and criminal justice institutions that developed nations have. So drug trafficking organizations can exploit these weaknesses, build up huge operations, and effectively wage war within developing countries.

What's worse, the drug war makes it harder for developing countries to build up these institutions. For one, the threat of violence is generally destructive and makes it tough for any of these countries to see the kind of meaningful economic growth that is necessary to build up institutions.

But the drug war also gives drug trafficking groups enormous profits — through the black market of prohibited drugs — allowing them to bribe, extort, blackmail, and finance a war against any government entity that poses a threat.

Developed countries have tried to alleviate all of these issues by helping developing countries finance their own war on drugs, such as the US-funded Merida Initiative for Mexico. But these measures either fail to suppress violence — as shown by Mexico's war on drugs, in which as many as 80,000 people have died — or shift violence to other countries that aren't getting as much support, as happened when drug trafficking operations moved from Colombia to Mexico and Central America after the US government helped Colombia crack down on drugs in the 1990s and 2000s.

The final result: a never-ending cycle of a violent trade-off that most Americans would consider unacceptable within our own borders, and that reversed Mexico's previous gains in life expectancy.