Cashin: Why it's not like 1998 all over again

The Russian ruble's dramatic fall on Tuesday may have triggered memories of 1998 for some—when a currency crisis caused Russia to default on its debt—but veteran trader Art Cashin isn't sold on the comparison.

From the collapse of hedge fund Long-Term Capital Management to fears of the Y2K bug, investors had a whole lot more to worry about in 1998, said Cashin, UBS' director of floor operations at the NYSE.

"There's a lot of different things," Cashin said on "Squawk on the Street." "It's not quite as leveraged as it was. If you remember we had kind of a cascading waterfall effect then. You had the Thai baht, then you went into the Russian ruble, and Long-Term Capital Management. ... And in the meantime the Fed was petrified of Y2K. So you had all that stuff coming together."

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However, Russian President Vladimir Putin could still offer investors a surprise in the form a fresh military operation, Cashin added.

"Mr. Putin may try to surprise everyone with some dramatic attempts," Cashin said. "Geopolitics [are] still out there. .... I think he quite honestly believes, and with some credibility, that NATO would not make any military move against him."

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