In 2002, he published a book on the September 11 terrorist attacks——in which Meyssan argues that such attacks were organized by a faction of the US military–industrial complex in order to impose a non-democratic regime in the United States and to extend US imperialism. The book was translated into 28 languages. It is one of "the first wave of book-length conspiracy speculations" in France and Germany about 9/11. His following book was Le Pentagate, a book arguing that the attack against the Pentagon was not carried out by a commercial airliner but a missile. The central thesis of the book is that a Boeing 757 did not hit The Pentagon. This was heavily criticised by other prominent 9/11 Truth Movement members such as Jim Hoffman. He started a campaign at the United Nations to initiate an international investigation commission to revisit the general consensus regarding the 9/11 attacks, but he was not able to reach his objective. There was little support, except from the Arab League and the Gulf Cooperation Council.
On 22 August 2011, Meyssan while stuck at the Rixos Hotel in Tripoli, reported live, by voice, to the Russian television network RT. He claimed that the Attorney General of the International Criminal Court was lying and that Saif al-Islam Gaddafi had not been taken prisoner. He also claimed that loyalist forces had regained ground. The next day, Saif al-Islam Gaddafi appeared in public, but the loyalists looted the land they had released. At the same time he described that he felt in danger, accusing other CNN and BBC journalists at the hotel of being spies from the CIA and the MI6, who were allegedly giving information on objectives to the NATO and the NTC militias. That same day, Meyssan reported that U.S. agents, disguised as journalists at the Rixos hotel had marked him for assassination. He then stated that the identities of these spies would be released in due course. Five countries offered protection to Meyssan and Mahdi Darius Nazemroaya in their embassies, but they were unable to reach any of them, because of the heavy fighting around the hotel and the encirclement of some of those embassies by NTC militias
Later activities
In November 2005, Meyssan presided over the Axis for Peace 2005 Colloquium, which gathered over 130 participants from 37 nations in order to discuss the international situation and call a people's mobilization in favour of international law and world peace and against the neoconservative trend. Meyssan believes the Beslan massacre was thought out and perpetrated by the CIA, through the terrorist leader Shamil Basayev, who Meyssan insists was a CIA strawman. The purpose of the massacre in Beslan had been, claims Meyssan, an attempt by the USA to gain control of the resources of the Caspian Sea. In recent times, he published several stories claiming Donald Trump is the victim of a "campaign that has been scientifically organized against the President of the United States", orchestrated "by the sponsors of Barack Obama Hillary Clinton". Meyssan is currently living in Damascus, Syria. He is columnist for the main Syrian newspaper, Al-Watan..
Works
La Protection des homosexuels dans le droit européen de Collectif, Projet Ornicar éd., 1993,.
L'Intégration des transsexuels de Collectif, Projet Ornicar éd., 1993,.
Charles Millon, le porte-glaive de Collectif, Golias, 1999,.
L'Énigme Pasqua, Golias, 2000,.
Terrorisme en soutane : Jean-Paul II contre l'IVG par le Réseau Voltaire pour la liberté d'expression, L'Esprit frappeur, 2000,.