With revelations continuing to emerge about Enrique Peña Nieto’s links to big business, the decision to allow him a state visit to the UK is misjudged

Britain will roll out the red carpet for the Mexican president, Enrique Peña Nieto, when he arrives for his state visit in March. The government sees Mexico as a “springboard into the Latin American market”.

However, today’s Observer interview with 19-year-old Uriel Alonso Solís should serve as an antidote to the hype that will surround the visit. Alonso survived the attack by police in Guerrero state on students who were then kidnapped and handed over to a drug cartel for execution. One of Mexico’s leading reporters on narcotics, Anabel Hernández, published evidence in Proceso magazine that federal authorities had been involved.

The case highlights an argument that journalists in Mexico have endeavoured to communicate for years (and for which scores have been killed): that the Mexican state is entwined with powerful quarters of the very cartels it claims to fight in its “war on drugs”. It is also poignant that the people who figure most among the 100,000 dead and 20,000 missing since 2006 are, like the students, from the poorest of the poor.

There are also ongoing revelations about Peña Nieto and his party’s links to big business, which are a major concern for anyone hoping to see Mexico rid itself of the endemic corruption that has bedevilled it over the years. Last year the government cancelled a £3bn rail contract with Grupo Higa when it was claimed that the president’s palatial family home had been bought with a massive mortgage from the group.

Something ties Britain directly to Mexico, and not in a good way. HSBC, Britain’s biggest bank, was caught – and admitted to – laundering hundreds of millions of dollars for the Sinaloa cartel, which has committed mass murder in Mexico and proliferated drugs and misery throughout the world. London is the laundering capital of that world and the question for heads of government is: which banks now handle the blood money? Might this be a topic of discussion for David Cameron and the president? I doubt it.

Peña Nieto’s visit coincides with concerns over Britain’s commercial proximity to Saudi Arabia, ideological cradle of extremist Islamism. The two instances prompt the question: who does Britain befriend in its quest for what are euphemistically called “trade” and “investment”?

We do not expect any of this to spoil the party very much, and that’s the point. It should.