The dollar should continue its appreciation as investors flock to the United States, and that’s not necessarily good news, says Mansoor Mohi-uddin, managing director of foreign exchange strategy at UBS.

“Policymakers need to be aware of shifts in the greenback’s position in the currency markets,” he says.

“Just over a decade ago, dollar strength during the Internet bubble caused the yen to weaken sharply, leading to the Asia crisis of 1997-98. The rise of the greenback also led indirectly to the Russia crisis of 1998 and forced Brazil to devalue the real in 1999,” he wrote in the Financial Times.

Fortunately, at present, the dollar remains a bit undervalued against the euro, Mohi-uddin says. The euro recently hit a 10-month low of $1.3267.

“But a period of greenback strength in the next few years, at a time when policymakers are lulled by a recovery in the global economy, may spark future crises in the currency markets.”

The dollar is gathering strength, as investors seek more risk in equities, commodities and emerging markets, Mohi-uddin explains.

“In short, the exchange rate markets seem to be undergoing one of their periodic ‘regime shifts.’”

Investment legend Jim Rogers sees things much differently for the dollar.

With the euro reeling, the greenback’s safe for now, he told Moneynews.com, noting that he owns it himself. “But in the longer term, the dollar is a terribly flawed currency” Rogers said.