It shook the world. But why do some suspect darker forces were at play?

Half of Americans believe they haven’t been told the whole story about 9/11. We’ve all heard the conspiracy theories, but why do they continue to grip some people so tightly?
Watch 9/11: Truth, Lies and Conspiracies and more acclaimed documentaries on BBC Select today. Restrictions apply*.
9/11: Truth, Lies and Conspiracies on BBC Select
In this thought-provoking exploration of one of America’s greatest tragedies, victims’ families, a senior politician and intelligence agency insiders discuss their belief that there’s much more to this story than we know.
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