The United States could be in for a major crisis if China and Japan lose their appetite for our government debt, hedge fund legend Julian Robertson says.

"It's almost Armageddon if the Japanese and Chinese don't buy our debt,” The founder and chairman of Tiger Management told CNBC. "I don't know where we could get the money. I think we've let ourselves get in a terrible situation, and I think we ought to try and get out of it."

Together, Japan and China hold a whopping $1.52 trillion of Treasuries. They are financing a U.S. budget deficit that may reach $2 trillion this year.

“If the Chinese and Japanese stop buying our bonds, we could easily see (inflation) go to 15 to 20 percent,” Robertson said.

“It's not a question of the economy. It's a question of who will lend us the money if they don't. Imagine us getting ourselves in a situation where we're totally dependent on those two countries. It's crazy.”

While Robertson doesn’t’ see China stopping its Treasury purchases, the Japanese may eventually be forced to sell some of their long-term bonds. “That's much worse than not buying,” he said.

Robertson isn’t the first expert to worry about a doomsday scenario in recent days.

Investment guru Marc Faber told Bloomberg, “I don’t know whether it will be tomorrow or in … 10 years. But the next crisis will bring down the entire capitalist system.”