Despite a campaign promise to see the lapsed ban renewed, Obama was bowing to the reality that to do so would be unpopular in politically key U.S. states and among Republicans as well as some conservative Democrats.
Mexican President Felipe Calderon, conducting an aggressive fight against drug cartels, had hoped to persuade Obama to push the reinstatement.
Obama, on a swift visit here meant to bolster Calderon in his drug fight, countered the disappointment for his Mexican host with a pledge to push Congress to finally act on an inter-American weapons treaty that has languished in the Senate since 1998. He said he is asking Congress to provide money for Black Hawk helicopters and surveillance equipment Mexico has long sought for its drug war.
"We are absolutely committed to working in partnership with Mexico to make sure that we are dealing with this scourge on both sides of the border," Obama said after meeting with Calderon.
"You can't fight this war with just one hand," he said. "You can't have Mexico making an effort and the United States not making an effort."
Obama's meetings with Calderon also spanned the economic crisis, immigration and clean energy.
But the escalating drug fight in, which is spilling over into the United States and alarming border communities, was the dominant topic.
Earlier, Calderon greeted Obama to the presidential residence, Los Pinos, with an acknowledgment of the costs "to turn Mexico into a safer country." Citing a visit a half-century ago by President John F. Kennedy, Calderon called for a new era of cooperation between the neighboring countries.
"In order for Mexico to grow and prosper, Mexico needs the United States' investments, and the United States of America needs the strength of the Mexican labor force," Calderon said.
The escalating drug fight in Mexico is spilling into the United States, and confronting Mr. Obama with an international crisis much closer than North Korea or Afghanistan. Mexico is the main hub for cocaine and other drugs entering the U.S., and the United States is the primary source of guns used in Mexico's drug-related killings.
Mexican drug trafficking organizations don't just pose a threat on the border, where the drugs enter the U.S., CBS News White House correspondent Bill Plante reports that the cartels now control virtually all of the retail distribution networks inside the U.S. - in large and small cities across the country.
But Homeland Security chief Janet Napolitano, also in Mexico City Thursday, told CBS Early Show co-anchor Maggie Rodriguez the reason for Mr. Obama's visit was "not about pointing fingers, it's about solving a problem."
She said both countries share "mutual" blame for the bloodshed - a comment Mr. Obama echoed Thursday.
Interviewed Wednesday by CNN en Espanol, Mr. Obama said Calderon was doing a "heroic job" in his battle with the cartels.
As for the U.S. role, Mr. Obama said, "We are going to be dealing not only with drug interdiction coming north, but also working on helping to curb the flow of cash and guns going south."
Napolitano said consultations with Mexico are "not about pointing fingers, it's about solving a problem: What can we do to prevent the flow of guns and cash south that fuel these cartels?"
Mr. Obama's overnight Mexican stop came on the way to the Summit of the Americas in the two-island Caribbean nation of Trinidad and Tobago, where he hopes to set a new tone for relations with Latin America.
"We will renew and sustain a broader partnership between the United States and the hemisphere on behalf of our common prosperity and our common security," he wrote in an Op-ed column printed in a dozen newspapers throughout the region.
In the past, Mr. Obama said, America has been "too easily distracted by other priorities" while leaders throughout the Americas have been "mired in the old debates of the past."
More than 10,000 people have been killed in Mexico in drug-related violence since Calderon's stepped-up effort against the cartels began in 2006. The State Department says contract killings and kidnappings on U.S. soil, carried out by Mexican drug cartels, are on the rise as well.
A U.S. military report just five months ago raised the specter of Mexico collapsing into a failed state with its government under siege. It named only one other country in such a worst-case scenario: Pakistan. The assertion incensed Mexican officials; Obama's team disavowed it.
|Photos: Mexico Border Violence|
Drug-related violence along the U.S.-Mexico border has spiked in recent months(Photo: AP)
Indeed, the Obama administration has gone the other direction, showering attention on Mexico.
Secretary of State Hillary Rodham Clinton said in Mexico City that the U.S. shared responsibility for the drug war. She said America's "insatiable demand" for illegal drugs fueled the trade and that the U.S. had an "inability" to stop weapons from being smuggled south.
CBS News chief foreign affairs correspondent Lara Logan recently wrote in the World Watch blog that Mexico essentially has two separate economies - the legal one and the illegal one, fueled by the narcotics trade and governed by the cartels. The problem, reported Logan, is that the cartels enjoy more wealth and more power than the country's legitimate leadership.
Mr. Obama has dispatched hundreds of federal agents, along with high-tech surveillance gear and drug-sniffing dogs, to the Southwest to help Mexico fight drug cartels. He sent Congress a war-spending request that made room for $350 million for security along the U.S.-Mexico border. He added three Mexican organizations to a list of suspected international drug kingpins. He dispatched three Cabinet secretaries to Mexico. And he just named a "border czar."
The Justice Department says such Mexican drug trafficking organizations represent the greatest organized crime threat to the United States.