On Wednesday 20 July 2011 at 10.35pm, I boarded Aeroméxico flight 033 in Mexico City to go to Barcelona. I was to connect from there to another Alitalia flight to Italy, where I was meeting friends to share experiences of Latin American struggles. The flight was going normally until a little after midnight, when the captain said we would be returning to Monterrey in Mexico because United States airspace had been closed off.

To my extreme surprise, when we landed at a little after 1am, a flight attendant asked for my identification and then asked me to collect my things and accompany her off the plane. When I got to the door a few Mexican federal police and two or three employees of Aeroméxico asked me to identify myself again, and to leave the plane. I told them I was not leaving until they explained what was going on. They said that "the United States government has refused the plane because you are on it".

I was astonished. A nice Aeroméxico person from Monterrey told me that they, too, were very surprised, and said they would see what could be done. I had no choice but to get off the plane. The federal police asked me to hand over a copy of my passport. I think the young women from Aeroméxico were as amazed as I was. We waited in the airport for an hour and a half until they were finally able to send the plane on its way. After that, they took me to a hotel. I was scared and very angry. I asked them to get me a seat on the first flight returning to Mexico City, which they agreed to do. I felt a kind of shock, a deep vulnerability, and I desperately wanted to get home to safety.

I was furious. How can these "United States authorities" behave with such despotism? How do they have the power to force a passenger off a plane that belongs to a foreign airline travelling to a country that is not theirs, leaving her in the middle of northern Mexico at dawn?

The US authorities should explain the danger that would have been caused if I had flown 30,000ft above America. I have flown over the US various times in the past few years without any problem, so is this a change in US policy? I want these authorities to explain how or why they decided what they did, because their decisions are not only foolish but also arbitrary. And do foreign airlines always submit passenger lists to the territories over which they fly, or just to the US, and since when? And is this sort of thing a frequent occurrence – how many others have been turned back in this way?

I think I am on a US blacklist, though I have never been told. Presumably I am blacklisted because I was arrested in Bolivia in 1992 as a result of my political activism. I was tortured and imprisoned and charged – together with Bolivia's current elected vice-president, Álvaro García – with belonging to a guerrilla organisation. The case was dropped due to the lack of evidence, and all charges against me were officially dropped in 2007.

Those of us who are on a US government "blacklist" – for a wide variety of often absurd reasons – are not asking that they let us into their country. It is aberrant to not let a plane through the air when we are travelling.

A great many commercial flights from Mexico to Europe pass over US airspace; is it to be the case that any Mexican the US chooses to blacklist has to find alternate routes? My concern is not just for me. Anyone – man, woman or child – who travels should be able to do so in the knowledge that they will not be arbitrarily stopped from reaching their destination.