A former senior member of the CIA has claimed David Cameron and Barack Obama "don't have a clue" about dealing with the war on terror.
At the Hay Festival in Powys, Michael Scheuer, ex-head of the CIA's Bin Laden unit, said the conflict in the Middle East was caused by US foreign policy.
He said extremists had no interest in western culture, but hatred stemmed from action in places like Afghanistan.
Asked what advice he would give Mr Obama, he said to "tell the truth".
Speaking on the fourth day of the Hay-on-Wye Festival, Mr Scheuer said: "American politicians, and I'm afraid listening to Mr Cameron this week, there's not a clue about what's going down in the western world.
"They can't cope with the fact that it's nothing to do with the way we live. It doesn't have anything to do with elections or democracy or liberty.
"We are being attacked in the west and we will continue to be attacked in the west as long as we are in Afghanistan, as long as we support the Israelis, as long as we protect the Saudi police state.
"Yet we hear the President, we hear your Prime Minister, talking about thugs and gangsters. We are still in the starting blocks in this war.
"The main recruitment sergeant for al Qaeda is Barack Obama because his speech on the May 19 was a declaration of cultural war on Islam."
Mr Scheuer left the unit hunting for Osama Bin Laden two years before the September 11 terrorist attacks in New York, but was later called back as an adviser.
He described his experiences in his book Imperial Hubris: Why the West is Losing the War on Terrorism, published in 2004.
On Sunday, an audience member asked him what advice he would give Mr Obama.
"I would ask him to tell the truth," he replied.
He added: "A president who was a statesman and a politician might say something like 'I'm sorry we've been kinda lying to you for 30 years and why we are being attacked is until recently we were supporting fascism across the Middle East'.
"In the rhetoric of our enemies there is very little, if anything, about attacking us for how we live or how we think or how we act in our own country.
"It is about intervention, it is about being in the Arab Peninsula and it has nothing to do with these cultural things.
"We are the ones that are arranging the cultural war against them. What we will see as al Qaeda evolves is that the next generation is better educated, combat experienced and probably much crueller."
Earlier, the former head of the British Army, Lord Dannatt, heralded May as "a bad month for evil men", following the killing of Osama Bin Laden and the arrest of former Bosnian Serb general Ratko Mladic.