In the year 2000, the world came together and committed to a short list of ambitious targets, which became known as the Millennium Development Goals (MDGs). The objectives — to reduce poverty, fight disease, keep kids in school, and so on — essentially boiled down to eight specific, verifiable goals. Over that decade-and-a-half, billions [were spent]. …For the poor and vulnerable, the world simply became a much better place thanks to the MDGs. …But in 2015… the United Nations came up with an absurdly long list of 169 targets for the Sustainable Development Goals. …Having 169 priorities is the same as having no priorities at all. We need to decide which targets matter most. …Promising peace is laudable, but it is likely impossibly difficult to achieve, and we don’t know how to get there. In contrast, we do know how to fix many pervasive problems effectively and at low cost.