"Curveball," the Iraqi defector who fed the Bush Administration bogus claims of mobile weapons labs being developed by Saddam Hussein -- claims that were later gussied up and presented to the United Nations as incontrovertible fact -- is finally explaining the tall tale that helped launch America's military.

"My main purpose was to topple the tyrant in Iraq because the longer this dictator remains in power, the more the Iraqi people will suffer from this regime's oppression," he recently told a filmmaker with the British Broadcasting Corporation (BBC).

That explanation will be featured on BBC2 this week, in one of Rafid Ahmed Alwan al-Janabi's first major interviews since speaking to The Guardian last year, when he finally came clean and admitted that his fabrications were seized upon by the Bush Administration, then sold as complete truth.

Al-Janabi's frightening tales of a reconstituted biological weapons program were so integral to the Bush Administration's case for war that they became the basis of General Colin Powell's testimony to the U.N. Powell has since walked that testimony back by explaining that the intelligence provided by al-Janabi was "shaky," but remained the best information they had at the time.

Powell's former top aide, Col. Lawrence Wilkerson, has spent years covering for Powell on that point, insisting that his former boss was misled by Vice President Dick Cheney, who allegedly cherry-picked intelligence to support the Administration's decision to invade.

"I think there was some manipulation of the material and there was some outright lying," Wilkerson told MSNBC last year, referring to how the Administration used al-Janabi's claims, despite a lack of evidence to support them.

Al-Janabi's explanation will be featured in the BBC2 series "Modern Spies," which exposes the secret lives of working spies around the world. The first part of the series aired Monday night.

Photo: Shutterstock.com, all rights reserved.