Government debt is a deferred tax on a country's citizens and their descendants. So it can be a real drag on future growth and, like credit cards, feels cost-free until the bill comes due. What's more insidious is that it is often run like a Ponzi scheme, in which current citizens benefit at the expense of their descendants.<p>But it is hard to say where the "point of no return" is for the U.S. Many countries have higher government debt as a percentage of GDP than the U.S. (<a href="http://en.wikipedia.org/wiki/List_of_sovereign_states_by_public_debt" rel="nofollow">http://en.wikipedia.org/wiki/List_of_sovereign_states_by_pub...</a>). Some of these high debt countries have reached their point of no return (Zimbabwe, Greece, Sudan) while others have not (Japan, Singapore). The U.S. is richer than all these countries and also has the advantage of a de facto worldwide dollar standard, so the U.S. is better able to withstand high debt loads than most countries. But then that's like saying the U.S. can afford to run up a huge credit card bill. The U.S. will feel richer than it is while charging, and the U.S. will be much poorer than it is once it pays it off.