Paul declined to offer a catalyst or even a timeframe for when the dollar “bubble” could pop, but did warn that it does happen, it will be quick and unexpected. “Most of the time, these things are unforeseen,” he said. “Did anybody warn us about 2007, 2008 in Lehman Brothers? Nobody warned us about that.”

According to Paul, the collapse of the dollar, and by extension, the stock market will likely come when the Fed begins to raise interest rates, something many expect it will do later this year. In his view, the Fed’s policies, and not real economic growth, have been the real reasons the dollar and U.S. equities have rallied. And the absence of those policies could lead to disaster.

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“Right now, the markets have tried to correct things since ’08 and ’09 but the correction has been prohibited,” Paul said. “It’s just like in the Depression; we prohibited, we delayed the inevitable.”

Of course, Paul has made similar bearish warnings in the past couple years, none which have really come to fruition. But his latest cries of caution come at a curious time. His son, the Kentucky senator, Rand Paul, recently announced his candidacy for the 2016 presidential election. But has he warned his son about this brewing “crisis?”

“I haven’t talked to him about that in recent months,” Paul said.