Neoliberalism is a new form of the old economic liberalism laid out in Adam Smith's famous capitalist manifesto, The Wealth of Nations, which was published soon after the Industrial Revolution. Neoliberals believe regulation should not be an impediment to manufacturing or commerce, and that high tariffs can be harmful. These ideas were liberal in the sense of advocating loose controls. In neoliberalism, profits are sought by lowering costs through improvements in the productive powers of labor. There should be reduced costly and unnecessary government regulation without sacrificing environmental protection and job safety. Neoliberalism has led to a widening gap between the rich and the poor, with the rich gaining wealth while the poor remain poor, justified by Social Darwinism. Neoliberalism is based on the uninhibited flow of capital without barriers, which many neoliberals use to protect their capital from taxes, or wealth the state uses to the benefit of all citizens. Neoliberalism also relies on the exploitation of many countries whose resources are sold out by corrupt leaders. For example, mineral rights in a poor African country could be sold to a wealthy Neoliberal whose company could use those resources to gain capital, while the citizens of that African country gain nothing, save its dictator, who gains a private jet. This is prime exampke of Neoliberalism's use of Karl Marx's Core-Periphery model, where the neoliberals are the core are those who exploit the periphery, who have no means to defend themselves. Periphery countries are reduced to providing labor, often at pay that is less than a dollar a day. Neoliberalism was espoused by both Ronald Reagan and Margaret Thatcher, and its policies of deregulation led to the global economic crisis of 2008.