Charles Nesbitt Wilson is not the sort of all-American hero that Hollywood tends to celebrate. The controversial former congressman had a string of affairs, took a belly dancer with him on government trips overseas, and was accused of snorting cocaine with strippers in a casino whirlpool bath. Yet he is portrayed by Tom Hanks in a heavyweight new film both as a buffoonish playboy, and a single-minded political visionary who helped to win the Cold War.

A member of Congress’s Defence Appropriations Subcommittee, Wilson was one of a handful of Washington lawmakers able personally to affect military budgets. A TV news bulletin from Soviet-occupied Afghanistan gave him his cause, and Charlie Wilson’s War shows how – in ways both fantastical and farcical – he worked in secret with the CIA to channel unspent defence dollars to Afghanistan throughout the decade.

It’s more than a bit weird,” the 74-year-old Wilson chuckles at seeing his life paraded on the silver screen, “it’s very, very, veryweird. I thought Tom Hanks was splendid. If anything, he made me look a little better than I am.”

But the movie is no act of hagiography. The screenwriter, The West Wing creator Aaron Sorkin, and the director, Mike Nichols ( The Graduate), leave plenty of ambivalence and ambiguity in a story that remains unresolved. Wilson, the CIA and the Afghans won the battle: the Soviet Army’s exit from Afghanistan was followed by the fall of the Berlin Wall and the collapse of the Communist bloc. But on September 11, 2001, what Wilson’s biographer, the late TV news director George Crile, called the “unintended consequences” of arming the Afghans became horrifically apparent. On the accusation that Wilson and his diverted millions helped to equip al-Qaeda, the former congressman is unrepentant, but conflicted.

“All of the hijackers on the 9/11 aircraft were Arabs, not Afghans,” Wilson argues. “A lot of them had trained there, but none of them were recruited there, and I think that’s important. George Crile thought that the victory over the Soviet Army gave the more radical Islamists the idea that they had defeated one superpower and they could probably defeat another. I don’t think that’s totally true, but I think it has merit.”

While Wilson never had any direct links with the Arab Mujahidin who formed the nucleus of al-Qaeda, he did tend to forge bonds with men whom history suggests he should have steered clear of. He was a supporter of Anastasio Somoza, despite the Nicaraguan dictator’s clumsy attempts to bribe him during their first meeting. He called the Afghan warlord Jalaluddin Haqqani “goodness personified” after Haqqani had given him a wartime tour of the region around Khost. Later the radical Islamist would be ranked No 3 on America’s post 9/11 most-wanted list after Osama bin Laden and the Taleban leader Mullah Muhammad Omar.

“That did give me pause for thought,” Wilson admits. “But Haqqani took care of me, and I’ll never forget that. I’d love to see him again. I would try to persuade him that the Taleban was a force for destruction – which he definitely wasn’t.”

The degree of Wilson’s influence is debatable. Steve Coll’s Pulitzer prizewinning Ghost Wars, the definitive investigation of the CIA’s pre9/11 role in Afghanistan, talks of Wilson only in passing, and with some disdain, while Tim Weiner’s recent (and highly critical) history of the CIA, Legacy of Ashes, does not mention him at all. But others have underscored Wilson’s importance. The 1980s chief of the CIA station in Islamabad, Milt Bearden, has spoken of Wilson changing history, while Zia, asked by 60 Minutes how the Afghan militias had defeated the Soviet army, simply said that “Charlie did it”.

“I’m comfortable with the way I believe history will judge what we did,” Wilson says. “History is not going to be so inaccurate as not to judge that our efforts were the ones that actually brought down the Red Army in Afghanistan. It’s too obvious. If we didn’t, who did?”

He is optimistic, too, that the film may help to refocus attention on a country whose future he still feels passionate about. “The Iraq war took a lot of the resources out of Afghanistan,” Wilson concludes. “There’s so much at stake: we must make it possible to establish a stable, forward-looking government there, or else we’ll have to do it all again. I think the film can [make a difference], and I hope that it does.” Charlie Wilson’s War is on general release

Explore Film

• Film Reviews

• Trailers

• DVD

• London Film Festival

Editor's choice

• The 100 Best Films of the Decade
• 70 facts you didn't know about Marvel
• The 50 Biggest Movies Of 2010