By TIM PADGETT WITH DOLLY MASCAREÑAS / MEXICO CITY Tim Padgett With Dolly MascareÑas / Mexico City – Thu Dec 31, 5:40 am ET

Forget 2012. As far as many Mexicans are concerned, the ancient Mayas were being generous: the sky's actually going to fall next year. Why? Because it's 2010, Mexico's bicentennial, and Mexican history has an eerie way of repeating itself. Mexico's 1910 centennial, after all, saw the start of the bloody, decade-long Mexican Revolution, which killed more than a million people. And that cataclysm was precisely a century after the start of Mexico's bloody, decade-long War of Independence in 1810.

You get the picture. As a result, there's been no shortage of talk lately about possible unrest, especially in the form of armed rebel groups, erupting south of the border in 2010. But is there really a basis for concern? None as apparent as the popular grievances that existed in 1809 or 1909. But this is still Mexico; and while Spanish colonizers no longer oppress the country, and dictators like Porfirio Diaz aren't brutalizing campesinos, the country nonetheless is reeling from the worst criminal violence in its history and one of its hardest economic slumps. "We are very near a social crisis," JosÉ Narro, the director of the National Autonomous University of Mexico (UNAM) in Mexico City, said recently. "The conditions are there." (Will the world end in 2012? What the Mayan prophecy is and how the movies see it.)

Mexican insurrections often do coincide with important dates. Most recently, Zapatista guerrillas in the poor southern state of Chiapas started a revolt on Jan. 1, 1994, the day the North American Trade Agreement (NAFTA) took effect. A big fear now is that Mexico's drug cartels, responsible for almost 15,000 killings in the past decade, are lending their resources and firepower to emerging guerrilla groups. If so, their plan may be to sow bicentennial terror and turn Mexicans against President Felipe CalderÓn's drug-war offensive. This past fall authorities say they seized an arsenal of large guns and grenades allegedly being sent from the Zetas, a vicious drug gang, to JosÉ Manuel Hernandez, a purported leader of the rebel group called the Popular Revolutionary Army (EPR). The EPR in recent years has claimed responsibility for attacks on Mexican oil infrastructure, including the bombing of six pipelines in 2007. (Hernandez denies the charges.) (See how Mexico took down a major drug lord and why it may not make much of a difference.)

At the same time, political observers like Denise Maerker, a prominent columnist for the Mexico City daily El Universal, fear that provincial governments in places like Chiapas, where the weapons were found, are using 2010 fears as a pretext for cracking down on social activists. "They're drawing questionable links between advocates for the poor and armed groups," says Maerker, who adds there's little evidence that Hernandez is an EPR boss. (See pictures from Ciudad Juarez, the most dangerous city in the Americas.)

Either way, the drug cartels have already shown they're willing to use high-profile national celebrations as a stage for narco-terror. Last year, during Independence Day festivities in drug-infested Michoacan state, narcos killed seven people with fragmentation-grenade blasts. Mexicans were rattled again in September when bombs went off at three Mexico City banks and another at a car dealership. No one was injured, but to many chilangos, or capital residents, the explosions seemed a warning of things to come.

Aside from inflated drug and guerrilla violence, another specter is unrest resulting from Mexico's deflated economy. Given its enormous reliance on the U.S. market - and on remittances from Mexican workers there, which have declined sharply this year - the global recession has hit Mexico especially hard. Its GDP, in fact, will contract more than 5% in 2009, exacerbating unemployment as well as Mexico's chronic poverty. A report this year by the Colegio de Mexico, one of the country's top universities, warned, "A national social explosion is knocking at the door." Said top Roman Catholic Bishop Gustavo Rodriguez, "We cannot separate the economic crisis from the violence and criminal crisis that we live day by day."

But while many fear the bicentennial year could galvanize that discontent, especially with the symbolic hype surrounding 1810 and 1910, CalderÓn insists the country will break the ominous century-cycle next year and make 2010 "a moment of peaceful transformation." Last month, he predicted next year will see "Mexico on a different trajectory toward development and progress." CalderÓn tried to get the ball rolling this month with a major political reform proposal that would allow re-election for Mexican office holders like mayors and legislators, a change he insists will give voters more power. It would still limit Presidents to one six-year term; but the move is significant, especially on the eve of 2010, because the ban on re-election was a pillar of the 1910 revolution.

Before CalderÓn can turn the bicentennial into a transformative engine, however, he has to get it jump-started. The economic crisis has forced chronic delays for a quarter of the more than 600 bicentennial projects Mexico had on the drawing board. Rather than being afraid of 2010, says Maerker, Mexicans are instead "just weary, especially of the economic situation." The year 2010 might not offer the fireworks of a revolution, but, unless Mexico can escape its general malaise, the bicentennial might see a quiet but dispiriting national devolution.