LAST March, after Mexican officials took offence at warnings from their American counterparts about security south of the border, Hillary Clinton travelled to Mexico City to repair the diplomatic damage. The secretary of state accepted blame for her country's demand for illegal drugs, recognised its need to control the southward flow of guns and cash, and vowed that the United States would be an equal partner in the “war” against drug gangs and organised crime declared by Mexico's president, Felipe Calderón. Some of those promises have been kept, in a modest way: over the past year, Barack Obama's administration has seized a little bit more drug money, begun to search southbound freight trains, examined its budget for trying to cut drug demand and raised it by 13%, and shared intelligence that led to the finding (and death) of a top drug trafficker.

But the drug “war” in Mexico has intensified, with 6,600 killings last year, up from 5,800 in 2008. This year has started badly. In the border city of Ciudad Juárez, 555 people have already died in 2010, compared with 449 in the first quarter of 2009. The violence is starting to strike innocents. In January 16 teenagers at a party were massacred in Juárez. Two students at Monterrey's Technological Institute were killed in crossfire this month; afterwards the traffickers organised roadblocks of stolen and torched vehicles, causing chaos in the city, Mexico's industrial capital.

In Reynosa the Gulf “cartel” and its former armed wing, the Zetas, concealed their violent split for weeks by threatening local journalists, killing one. Residents were reduced to finding out about the gun battles they heard nearby on Facebook and Twitter. On March 13th the traffickers broke a taboo against taking on the United States. In simultaneous drive-by shootings, gunmen killed a visa worker at the American consulate in Juárez, along with her husband and that of another employee there.

Faced with such a grim panorama, this week Mrs Clinton returned to Mexico City, accompanied by the entire American national-security team. She reiterated many of the same arguments. But this time both sides wanted more than soothing rhetoric.

After three years of throwing some 50,000 troops against the drug gangs, Mr Calderón is now trying to broaden his strategy. In tandem with American officials, his government has announced a new plan to fight organised crime. This will be enacted in pilot programmes in Juárez and Tijuana, the two biggest border cities. It includes customised attempts to dismantle each gang through intelligence; spending on social development in violent areas; and a promise to speed up a glacial effort to overhaul police forces and the courts.

All of this will require far greater teamwork with the United States. American officials say that the new plan calls for more intelligence sharing, with “fusion centres” where American agents are embedded with Mexican analysts. American police will step up training and vetting of their counterparts. To try to prevent security worries clogging cross-border trade, American customs officials may be posted throughout Mexico. “Secure corridors” would be set up where goods could be tracked to the border. Mrs Clinton announced that the Mérida Initiative, a $1.3 billion anti-drug aid effort for Mexico involving hardware and training, will be followed by $331m for social programmes and to strengthen the courts.

In the past this closer American involvement would have prompted Mexican outrage over the violation of its sovereignty. The mood is changing. In the run-up to Mrs Clinton's visit both Mexico's ambassador to the United States and the general in charge of its defence college declared that the country needed international help to win the drug war. “It was unprecedented for a high-level member of the Mexican army to say that,” says Denise Dresser, a political scientist at ITAM, a Mexico City university. “But the situation has gotten so bad that you're starting to see a wearing down of that reflexive, historical anti-Americanism.”

Yet compared with the $18 billion-39 billion that the drug gangs are officially estimated to send south each year, American aid to Mexico remains small. And only $128m of the money promised under the Mérida Initiative, signed in 2008, has been disbursed.

American officials point to the relative success of Plan Colombia, a much bigger aid programme, in reducing drug-related violence in that country. But Mexico poses some unique difficulties. It is bigger and richer but more decentralised, with weaker police forces and courts. Colombia has let several hundred American military advisers operate in its territory. Some of the training of Mexicans takes place in the United States. Mexican officials refuse to put American agents in operational roles. “That takes a lot of options off the table,” says Scott Stewart of Stratfor, an intelligence consultancy. “There's only so much you can do in the classroom instead of out on the streets.” And the Obama administration has ruled out seeking a new ban on the sale of assault weapons in American gunshops—the main source of the mobsters' weaponry.

The new strategy looks more promising, but as always success will depend on implementation. Polls suggest that Mexicans' previous support for Mr Calderón's crusade against the drug gangs is wearing thin. In one recent poll only 21% of respondents said that it had made the country safer, whereas half thought it had heightened the danger. Mr Calderón's term ends in 2012, and his successor may not be equally committed to vanquishing organised crime. The new long-term plan will have to show some short-term results.