To encourage investment, the government needs to find a way to credibly recommit to letting investors keep their money if they succeed. Mainly, that involves appeasing the confidence fairy by making it clear how the country will pay its bills. Generally speaking, markets allocate resources better than governments, so the more government spending is held down, the better the economy does. The 1990s, a rare oasis of fiscal discipline and (as a result) a booming economy, are the example to emulate. But for a given trajectory of spending, it’s better to know how it will be paid for, so that private sector actors can plan around it, than for the economy to be burdened with the uncertainty that deficits create. All this is fairly easy to see, once you take off the Keynesian spectacles.