Mexico has recently announced that the government will begin a program of cooperation with the armed vigilante goups ("autodefensas") that have sprung up in the western pa of the countr to combat the drug cartels, most specifically the Knights Templar.

But some are urging the government to be cautious, reminding that similar pacts have gone astray not so long ago in Mexico's southern Latin American neighbor, Colombia.

Like Mexico, Colombia also faced the daunting task of dealing with drug cartels that were at least as well financed as the authorities that were supposed to keep them in check. Like in Mexico, Colombia also saw the rise of civil militias when government forces were unable to protect the citizenry in the way the citizens thought was sufficient.

And, some worry, when the cartels were removed from the immediate threat that they posed in the beginning, the militias moved to fill the power vacuum in rural Colombia, and became a threat themselves.

Many analysts are now calling on the Mexican government to take preventative steps to make sure that the same scenario doesn't play out again, farther to the north.

"At this point in the crisis the most viable option is not to remove the self-defense groups, but to offer an institutional arrangement that serves to regulate their interactions with the state," writes national security consultant Roberto Arnaud on the InSightCrime blog. "History shows that the uncertainty of the Colombian state towards self-defense forces generated huge costs. Unfortunately, Mexico seems to be following a similar path."

Arnaud notes that cooperation between the military and the civil defense forces in Colombia did not end with the break-up of the super-cartels in the 90s, but continued for some time afterward, confirmed by later releases of U.S. intelligence as well as journalistic observation. The civil defense paramilitaries in Colombia continued to operate, carrying out kidnappings and executions.

"An emblematic incident occurred in the summer of 1999, when the United Self Defense Forces of Colombia (AUC) -- the national paramilitary umbrella group -- stormed the towns of La Gabarra and Tibu to eliminate the guerrillas operating in the area," Arnaud writes. "The clashes between guerrillas and paramilitaries lasted for three months and produced nearly 150 dead; the armed forces, stationed a few miles from the location, did not intervene."

Observers are hoping that the same situation does not repeat itself in Mexico.