You hardly need to be mentally ill to reach this conclusion. Sure, it's not like there's a grand master plan nailed to a wall somewhere. But to conclude governments helped create this situation all you need to do is read about the background of the attackers. Their radicalisation started due to the US invasion of Iraq. When the attackers tried to go to Iraq to fight against the occupation they were arrested and thrown in prison, where they met a radical Islamist.
No war? Probably the chain of events that led to the attack would never have happened. Our governments will continue to be in denial about this because politicians feel they should be able to engage in arbitrary foreign "policy" (i.e. invasions, occupations, picking winners in regional conflicts) without any kind of repercussions or blowback at all. When reality refuses to go along with this notion they claim it's an outrage and the solution is to record more telephone calls.
From the article:
The Buttes-Chaumont group’s jihadi aspirations were directly linked to the second Iraq war in 2003. They would sit in apartments watching footage of the US-led invasion. “Everything I saw on TV, the torture in Abu Ghraib prison, all that, that’s what motivated me,” one of Kouachi’s friends told their trial.
But under Jacques Chirac, France had refused to intervene in the Iraq war and the young cell’s stance wasn’t really a movement against the French state. It was more a rage directed against the US. Some of the group stated that jihad wasn’t done in France. The focal point was fighting a foreign invader in Iraq.
“They were the pioneers of French jihadiism,” said Jacques Follorou, a journalist at Le Monde and author of the book Democracy under Control, the Posthumous Victory of Bin Laden, about security issues
A bit later in the same article
Kouachi, who scraped a living delivering for El Primo Pizza on the other side of the ring-road that serves as a moat around Paris, was arrested in January 2005 on his way to catch a flight to Damascus, believed to be ultimately heading for Iraq
..... He got a relatively light prison sentence, three years with 18 months suspended, as there was little hard evidence against him except a plane ticket for Damascus.
After his arrest while trying to fly to Damascus in 2005, Kouachi was on remand in the notorious Fleury-Mérogis prison south of Paris, a super-size decaying concrete mega-jail, which is Europe’s largest prison
..... He added that when the young men were arrested and held on remand before their case in 2008, prison gave them access to a universe never known before. “If the Butte-Chaumonts was an informal school of jihad, prison was the superior diploma.”
One of the prisoners involved in publicising the terrible conditions [in the prison] was Amédy Coulibaly. He was an armed robber on his third sentence, this time for robbery, receiving stolen goods and using false number plates. Coulibaly met Kouachi inside the prison and they became close during seven months on the same wing – prisoners from similar backgrounds and affinity were kept together on the same blocks, which allowed them to convene. Less than a decade later, Coulibaly joined the Kouachis in last week’s terrorist attacks
.... In prison together, Kouachi and Coulibaly found not only friendship but a mentor who radicalised them