Let us bid us a fond farewell to Mexican president Enrique Peña Nieto, who has been in the UK this week as part of a state visit. During his time here, he has travelled across the country, from London to Aberdeen, meeting the UK’s most important representatives including all three party leaders and the Queen, and has signed a “Memoranda of Understanding on Collaboration in the Energy Sector”, with representatives from the UK oil and gas industry.

The Queen spoke of the “enduring friendship” between Mexico and the UK, Nick Clegg remarked that he hoped the visit would usher in a “new era of UK-Mexico relations which will bring our people even closer together”, and FCO minister Hugo Swire tweeted that he had found Peña Nieto’s speech “inspiring”.

Even by the tawdry standards usually applied to British relations with Latin America, this takes some doing. Mexico is in the grip of an urgent human rights crisis, with Amnesty International describing torture as “out of control” and accusing police and security services of having “blood on their hands”. More than 100,000 people have been killed and more than 22,000 have disappeared since Mexico launched a “war on drugs” in 2006. The most recent outrage in Mexico has been the disappearance and probable massacre of 43 students in Ayotzinapa, which Peña Nieto insisted had nothing to do with the Mexican authorities – despite growing evidence to the contrary.

The kindest thing one could say about Peña Nieto with regards to the students of Ayotzinapa, the drug war, the murder of thousands and the threats to journalists who try to expose these crimes, is that he has been totally incompetent, unforgivably slow to react, and has failed to adhere to even the most anodyne of his pre-election promises to approach the problems with narcotrafficking from a less militaristic standpoint. This failure means Mexico’s security services are still armed to the teeth, making it easier for them to commit exactly the sort of human rights violations condemned by Amnesty International and other human rights groups across the world.

In light of these facts, David Cameron’s vague assurance that he would “raise the human rights issue” during Peña Nieto’s UK visit is laughable. The prime minister rightfully expresses horror when Isis militants behead captives to send a message to the west, and yet welcomes with open arms the president of a country in which innocent people are publicly beheaded by drug cartels in their hundreds, protected by a culture of silence and indifference.

And yet we should expect nothing less from the west’s attitude towards Latin America, which has been characterised by this kind of hypocrisy for centuries. Across the region, the US in particular has been unrestrained in its meddling with Latin American governments, frequently installing or befriending tyrants that submit to its will and then denouncing them as soon as they cease to be useful. Even now, the UK and the US are engaged in brazen hypocrisy in their attitudes towards the region – like, for example, Hugo Swire promising that he does not “turn a blind eye” to human rights violations in Colombia (our other unsavoury Latin American ally) at the same time as the Colombian press was reporting that the UK was providing specialist training to the notoriously violent Colombian military. The UK Foreign Office is yet to clarify its position on that.

Similarly, US Congress is preparing to issue sanctions against Venezuela for human rights violations committed by the security forces during protests last year; an incredible feat of double standards, given that even Venezuela’s harshest critics would concede the human rights situation there isn’t even close to the crisis in Mexico, or – for that matter – Colombia. Far more likely the US is unhappy with Venezuela’s hostility towards it, as well as its pivotal role in setting up a network of Bolivarian socialist governments across the region (including Bolivia, Ecuador, Cuba, Nicaragua) which have made it their mission to extricate themselves from economic dependence upon the country.

Those who defend our foreign policy in Latin America would probably invoke realpolitik; they might argue that the west’s hypocrisy is justifiable, given the need for nations to look out for their own interests. Whatever the reason, we shouldn’t be under any illusion about the consequences of our double standards. It’s not socialist leaders like Fidel Castro or the late Hugo Chavez who suffer from our actions; it’s the region’s poorest and most vulnerable people – like those 43 Mexican students.

We owe it to them to do things differently.