The economy may finally be ready to expand more than 2 percent, helped by the Federal Reserve's tapering of its quantitative easing (QE), says David Malpass, president of Encima Global research firm.

The economy hasn't been able to breach that level for a sustained period since the recession ended four years ago.

"The likely culprit for the severe post-2009 weakness is that the federal government and Federal Reserve chose to go on an expansionist tear that scared off private investment and hiring," Malpass, a former Treasury Department official, writes in The Wall Street Journal.

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But now the government and Fed are starting to move in the right direction, he says, and "the economy is showing signs of life."

As for the central bank, its Chairman Ben Bernanke said last month that that it might start cutting its $85 billion of monthly bond purchases this year and end them by mid-2014.

"An end to the latest version of the Fed's quantitative easing would create space for more growth in private credit and a shift back toward market, not government, allocation of credit," Malpass explains.

"The Fed's turn away from its extreme policies would also allow fairer interest payments to savers, who are bearing most of the burden and risk from artificially low interest rates," he adds.

"In the U.S., any movement to encourage growth would be a positive surprise and a catalyst. ... The small policy relief under way may be enough to break the U.S. out of the new normal of the past several years and ignite the world's largest, most profitable and innovative private economy."

Half of 54 economists surveyed by Bloomberg expect the Fed to shrink its bond buying to $65 billion at its September policy meeting. That idea is no longer roiling financial markets, with bond yields stabilizing over the past two weeks.

"The markets have adjusted to the new information," Russell Price, senior economist at Ameriprise Financial, tells Bloomberg. "Investors believe it won't be a strong negative for the markets or the economy."

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