If you've ever suspected politics is increasingly being run in the interests of big business, ... Jeffrey Sachs, a highly respected economist from Columbia University, agrees with you - at least in respect of the United States. In his book, The Price of Civilization: Reawakening American Virtue and Prosperity, he says the US economy is caught in a feedback loop. ''Corporate wealth translates into political power through campaign financing, corporate lobbying and the revolving door of jobs between government and industry; and political power translates into further wealth through tax cuts, deregulation and sweetheart contracts between government and industry. Wealth begets power, and power begets wealth,'' he says. Sachs says four key sectors of US business exemplify this feedback loop and the takeover of political power in America by the ''corporatocracy''. First is the well-known military-industrial complex. Second is the Wall Street-Washington complex, which has steered the financial system towards control by a few politically powerful Wall Street firms, notably Goldman Sachs, JPMorgan Chase, Citigroup, Morgan Stanley and a handful of other financial firms. Third is the Big Oil-transport-military complex, which has put the US on the trajectory of heavy oil-imports dependence and a deepening military trap in the Middle East, he says. Fourth is the healthcare industry, America's largest industry, absorbing no less than 17 per cent of US gross domestic product.