The U.S. is headed for a major debt crisis, Marc Faber says.

It won't hit us this year or next year. But within 5-10 years, the United States will be forced to quietly default on its debt, most likely by printing money and destroying the value of the currency.

The main problem comes down to two things: 1) ballooning debts and 2) future interest costs.

As these charts show, in the past decade, the U.S. government's total debt and liabilities have gone through the roof, especially when Fannie, Freddie, Medicare, and Social Security are taken into account. This trend is unsustainable, and it will correct itself only through a rapid acceleration of economic growth and tax revenues, a new-found financial discipline, or a crisis--or a combination of all three.

The second problem is interest costs. Right now, the government's debt and deficits aren't creating an undue burden because the government can borrow so cheaply. Eventually, however, as the country's financial situation gets weaker, interest rates will likely rise, and our interest costs will go through the roof.

According to Faber, our annual interest costs currently amount to 12% of the government's tax revenue. Within five years, Faber estimates, these costs will soar to 35% of tax revenue. This will force the government to cut spending (unlikely) and/or frantically print money.