Is Mexico City safe from drug cartel war -- or the next target?

A truck carries troops through the historic center of Mexico City, where major cartel violence has not been a part of daily life.

Near the ruins of an ancient Aztec temple, a woman shouting into a microphone claims Mexican society is crumbling.
"We are no longer free to walk in the streets because of what is happening," she yells.
Demonstrators behind her tape cardboard crosses to a fence in front of Mexico's National Palace. The names of slaying victims are scrawled with black magic marker on each one.
"I want the impunity to end," a leftist lawmaker says, blaming Mexican President Felipe Calderon's five-year-long crackdown on drug cartels for the surge in violence.
A handful of people clap. But throngs walk through Mexico City's massive central square without glancing in his direction.
In this sprawling metropolis, the brutal conflicts between drug cartels and government troops are both strangely absent and omnipresent. They are nowhere to be found and everywhere you look.
At a corner newsstand, the front page of a paper shows a dead man lying in a pool of blood. The cover of a magazine pictures people praying at a funeral.
At an airport gift shop, a book about beauty queens in the drug trade is only steps away from bottles of tequila and souvenir sombreros.
From the halls of his official residence here, President Calderon announced plans in late 2006 to deploy troops in a nationwide crackdown on drug cartels.
Here, too, a peace movement led by a poet whose son was slain has taken root, with protesters staging "caravan" demonstrations that go from the city's central square to some of the country's most violent areas.