The Tories had spent 13 years in the wilderness when Cameron became leader, promising a transformation. He half succeeded, and so half won an election. Though he looks at ease in the office of Prime Minister, suspicions remain whether the polished exterior contains a solid credo - or whether it might be hollow. Cameron would like to be known as the architect of the "big society", a renaissance in civic engagement. He is more likely to be remembered for using Britain as the crucible for an ill-advised experiment in trying to provoke growth by subjecting a weak economy to extreme austerity. History will recognise him for having run Britain's first coalition government since 1945. That, however, is a consequence of his biggest failure - the inability, in an open-goal election, to secure a parliamentary majority.
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