It would probably be wrong to predict that the Turnbull government’s decision to build an airport at Badgerys Creek will be a white elephant. It is more likely to be a large, white, steppe mammoth. Common sense should have told the politicians that if the company which enjoys the existing airport monopoly had worked out that this is risky, how on earth could they think that they could make it profitable? Instead of waiting until the private sector judges a second airport worthwhile, politicians in this and future governments will now borrow many more billions than the $6 billion indicated,...