"The Oxford-educated Mr Fisher, an outspoken free-marketer and believer in the Schumpeterian process of "creative destruction", has been running a fervent campaign to alert Americans to the "very big hole" in unfunded pension and health-care liabilities built up by a careless political class over the years. "We at the Dallas Fed believe the total is over $99 trillion," he said in February. "This situation is of your own creation. When you berate your representatives or senators or presidents for the mess we are in, you are really berating yourself. You elect them," he said. His warning comes amid growing fears that America could lose its AAA sovereign rating."