"There's a huge bubble with the dollar," Paul said on Tuesday's "Futures Now." The Dollar index, which measures the dollar against a basket of other major currencies, is near 12-year highs as the Fed has retreated from its stimulative programs at just the same time that other central banks have introduced their easing measures. But rather than take the rally as a sign that investors see strength in the U.S. economy, the outspoken former congressman sees the dollar's massive move higher as simply a byproduct of a world awash in easy money.

"It's not so much that the dollar is a great currency. It's the fact that nothing else is any better, said Paul. "The fundamentals are a disaster. The economy is in bad shape when you have more than half the people hardly making ends meet." 

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."