The ruble's plunge — it has dropped 46 percent against the dollar since the beginning of the year — endangers the global financial system, says Wolfgang Koester, CEO of currency research firm FiREapps.
"The downward spiral of the Russian ruble has exacerbated global currency volatility, and it has a contagion effect," he writes in a commentary for
CNBC.
For example, the ruble move should reinforce Japanese Prime Minister Shinzo Abe's determination to devalue the yen, Koester says. The dollar hit a seven-year high against the Japanese currency earlier this month.
"The threat of a race-to-the-bottom, beggar-thy-neighbor currency war is very real," he writes. "The contagion also exposes continuous fundamental weaknesses in global markets. Structural weaknesses in the eurozone, for instance, portend further declines for the euro."
The greenback reached a two-year peak against the European currency earlier this month.
As for Russia, if it doesn't soon show a willingness to compromise over its intervention in Ukraine, "then we will likely see a repeat of the 1998 collapse of Russia's economy," Koester notes. And, "this time, it would be worse."
"The implications of the ruble's slide extend to other central banks as well. The ruble crisis has made Federal Reserve Chair Janet Yellen's job more difficult. It's still unclear what impact the ruble's slide and its spreading contagion will have on a strengthening U.S. economy."
In star investor Jim Rogers' eyes, a currency war already has begun, thanks to central bank easing in many countries.
"Whether it's an intentional war or an accidental war or side effect, I don't know, but it's certainly happening. Just look around, you see that nearly every currency in the world is down a lot against the U.S. dollar,"
Rogers tells Wall Street Daily.
"I don't know if somebody sat around and plotted, 'Let's have a currency war.' They just said, 'What we need to do is print a lot of money,' without realizing it's going to cause currency fluctuations."