"There's a time bomb in there somewhere"

With the government planning to roll over its short-term loans into more stable, long-term securities, experts say investors are likely to demand a greater return on their money, saddling taxpayers with huge new interest payments for years to come. Some analysts also worry that foreign investors, the largest U.S. creditors, may prove unable to absorb the skyrocketing debt, undermining confidence in the United States as the bedrock of the global financial system.