Neither President Barack Obama nor his GOP challenger Mitt Romney are offering specific plans to improve the economy, and both are at risk of fueling populist anger among a frustrated public, said Mohamed El-Erian, CEO of Pimco, manager of the world’s largest bond fund.

In the U.S. both Obama and Romney have yet to offer concrete solutions to dealing with a weak labor market, problematic public finances, a broken credit system, inadequate infrastructure and a lagging education system, El-Erian wrote in Foreign Policy.

Failure to address structural problems hindering recovery could spark anger and backlash among voters.

Editor's Note: 'It’s Curtains for the US' — Hear Unapologetic Warning from Prophetic Economist. 

“The risk for the United States, as well as the global economy, is that a lack of vision and political courage ends up leading to even greater economic disappointment and financial instability, bringing with it the social unrest we’ve seen in so many other countries over the past 18 months,” El-Erian wrote.

“Occupy Wall Street and the Tea Party may have somewhat fizzled, but populist anger could return with a vengeance.”

The U.S. economy officially emerged from recession in 2009, yet growth rates have remained tepid and unemployment rates have remained high.

Uncertainties over the U.S. and global economies in general, as well as concerns surrounding upcoming fiscal adjustments, have kept investing and hiring at bay.

In the United States at the end of this year, tax breaks expire at the same time cuts to government spending kick in, a one-two punch known as a fiscal cliff that could send the country right back into recession if Congress fails to deal with the problem.

Europe, meanwhile, remains mired in its debt crisis, while the Chinese economy appears to be cooling its once red-hot growth rates.

Fear in general is punishing the U.S. recovery.

“The longer America’s interlocking economic and political challenges persist, the greater the number of companies and long-term investors that begin to worry — and, more importantly, act on those fears. They hire fewer people and invest less in factories and equipment,” El-Erian wrote.

“As they increasingly sit on the sidelines, the country’s fate will be left in the hands of tactical position players and short-term traders, further ramping up volatility and reducing future growth and job opportunities. And when day traders and company flippers start running a country’s economy, watch out.”

Lawmakers have suggested they may let the fiscal cliff approach and then quickly deal with it on a retroactive basis early in 2013 after elections, though confidence is ebbing and fears are building.

A Wall Street Journal poll of economists found that Congress failed to deal with the fiscal cliff, it would subtract 2.2 percentage points from 2013 growth, most of which would occur in the first half of the year.

The survey respondents expect the economy to grow 2.4 percent next year assuming a deal is reach and the cliff is averted.

“It would cause a recession if not dealt with at all,” said Robert Mellman of JPMorgan Chase.

Editor's Note: 'It’s Curtains for the US' — Hear Unapologetic Warning from Prophetic Economist.