Pope Francis' six-day visit to Mexico will see him touch down in a complex country facing enormous challenges because of social inequality and the violence attached to its powerful drug cartels. At the same time Mexico is financially vibrant, with the second largest economy in Latin America, and has a booming tourist industry.

The inequalities he will see will be of concern to Francis, who has made care for the poor a recurring theme of his papacy. According to the OECD, Mexico has the world's second highest degree of economic disparity between the extremely poor and extremely rich, after Chile; it also spends about a third of the average on poverty reduction.

It's this inequality that is fueling the drug war that the government shows no signs of winning; a large pool of low-skilled and poorly-educated people ensures a flow of foot-soldiers into the business. In 2012 it was estimated that Mexican cartels employed 450,000 people directly and a further 3.2 million people's livelihoods depended to some extent on the drug trade.

Some of Mexico's priests have been on the front line of the drug war. Others, including among the heirarchy, have been less keen to speak out. However, Pope Francis has made it crystal clear where he stands. In a video released by the Vatican last week he said: "The Mexico of violence, the Mexico of corruption, the Mexico of drug trafficking, the Mexico of cartels, is not the Mexico our Mother [Mary] wants."

In an interview with Mexican news agency Notimex State he said he hopes to be a messenger of peace, which must be fought for daily.

"Violence, corruption, war, children who cannot go to school because of their countries at war, trafficking, arms manufacturers who sell weapons so that the wars in the world can continue," he said: "More or less this is the climate in which we are living in the world today.

"It is obvious that I cannot do it alone, it would be crazy if I said that, but with all of you, an instrument of peace," he said, adding that peace is something that is "kneaded with your hands" every day through small gestures of charity.

"Peace is born from tenderness, peace is born from understanding, peace is born or made with dialogue, not in rupture," he said. However, this doesn't mean Francis is unwilling to confront: when he travelled to southern Italy in 2014 he made a point of excommunicating members of the Italian Mafia, and he made take a similarly strong line in Mexico.

He is scheduled to arrive in Mexico this evening after his historic meeting with Patriarch Kirill, head of the Russian Orthodox Church. He will meet Mexico's bishops and celebrate mass in the Basilica of Guadeloupe, where the Virgin of Guadeloupe is venerated. In Mexico City he will visit a paediatric hospital; he will spend time with indigenous people and young people, and visit a prison. The latter visit will come against the background of a recent tragedy: a battle between rival drug gangs at a prison yesterday killed 52 people in the northeastern Mexican city of Monterrey. The incident was one of the worst in a series of deadly riots in recent years to rock the country's overpopulated prisons, which often house inmates from different drug cartels.

He will also visit Cuidad Juárez, the border town known in the past for its horrific rate of murder and sexual violence, and celebrate an open-air cross-border mass there. About 200,000 people are expected to attend the Mass on the Mexican side of the border with some 50,000 more people in Texas. The mass will be seen as a challenge to the anti-migrant rhetoric used by Republican contenders for the presidential nomination and as a challenge too to the conservative elements of the Mexican Catholic Church, to whom the Pope's habitual outreach to the poor and marginalised is foreign.