By Fareed Zakaria, CNN

The drug wars dominate the discussion in Mexico and in many border states in America as well. There have been nearly 50,000 drug-related killings in Mexico since President Felipe Calderón began his six-year term. That's more than twice as many civilian deaths in the same period in Afghanistan.

Calderón is widely viewed as having blundered in taking on the drug cartels. But I have always admired his courage in doing so. And it might just be paying rewards.

Robert Bonner is a former U.S. drug enforcement official and he's also served as a commissioner of U.S. Customs and Border Protection. In a recent op-ed as well as a forthcoming Foreign Affairs assay, Bonner argues that despite the negative headlines, President Calderón has made huge gains against the drug lords.

Bonner's point is that when Calderón came to power, Mexico's half-dozen cartels were making up to $10 billion in annual revenue from drugs alone. They bribed officials and the police. Those they could not bribe, they killed. Calderón had no existing means to defeat them so he enlisted the military, a group force that could target cartel leaders and win in an all-out gun battle.

Fifty thousand lives is a heavy price to pay, but this was never going to be an easy war. The cartels had almost taken over Mexico. (More: Mexico drug war – Bodies for billions)

Now the data proves Bonner's point. It seems the tide is finally turning. Using Calderón's strategy, the Mexican government has killed more than 40 major cartel members. The Economist magazine points out that between 2007 and 2008, the number of drug-related killings in Mexico rose by 29 percent. In the next two years, it rose by 22 percent, then by 28 percent. Last year, however, there were signs of a plateau with only an 8 percent rise.

With many cartels now severely weakened, that number could fall further. A Pew poll conducted last spring shows that 45 percent of Mexicans believe the government is making progress against the cartels; 83 percent support Calderón's strategy of using the army to fight them.

When a government forcefully commits to take on an internal terrorist or drug group, it usually wins. This is what happened in Colombia over the last decade and it will likely happen in Mexico over the next few years as long as Calderon's successor stays with the fight.

The Mexican elections begin in July and Calderón steps down in December. If Mexico's children are indeed to grow up in safer conditions, then its leaders need to continue to press on in the war on drugs.

Even Mexicans who have lived with the violence agree on one thing - some action is better than the previous policy of no action at all.

Of course, success in Mexico probably means the cartels will move to Central America. Guatemala is already becoming the next frontier.

You see, then the richest country in the world has an insatiable demand for drugs. Someone is going to produce them and meet that demand...but that's for another post.