The CIA calls it ‘blowback’, when the unintended consequences of what seemed like a good policy at the time come back to bite you. The classic example is Western sponsorship of radical Islamist fighters against the Soviet occupation of Afghanistan in the 1980s. That covert war against the Kremlin was a significant factor in crippling Communism in Russia which was a good thing, surely? It certainly seemed cost-free for America — until that bright morning of September 11, 2001, when Afghan-based...





