Perhaps the "Oracle of Omaha" should be rechristened as the Optimist of Omaha instead.

Tucked into Berkshire Hathaway's 2015 annual report was a pointed dismissal by Warren Buffett of the growing refrain that the U.S. economy would fail to provide a better lifestyle for future generations than it has in the past.

As the 2016 presidential campaign kicks into high gear, high levels of debt, stagnant earnings and income inequality are frequently mentioned by candidates—including former Secretary of State Hillary Clinton, a candidate Buffett has publicly supported.

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"It's an election year, and candidates can't stop speaking about our country's problems (which, of course, only they can solve). As a result of this negative drumbeat, many Americans now believe that their children will not live as well as they themselves do," Buffett wrote in Berkshire's annual letter.

"That view is dead wrong: The babies being born in America today are the luckiest crop in history," declared Buffett, one of the world's wealthiest men with an estimated net worth in excess of $60 billion.

Buffett highlighted data that showed U.S. per capita growth is six times higher currently than it was in 1930, the year of his birth. Those gains are the byproduct of productivity and efficient work, he said.

"U.S. citizens are not intrinsically more intelligent today, nor do they work harder than did Americans in 1930. Rather, they work far more efficiently and thereby produce far more," Buffett added. "This all-powerful trend is certain to continue: America's economic magic remains alive and well."

The U.S.'s surging entitlement spending and its seemingly intractable debt have stoked widespread concerns about insolvency, and the inability of the federal government to meet its future obligations. Buffett, however, was hearing none of it.

"For 240 years it's been a terrible mistake to bet against America, and now is no time to start," the billionaire wrote.

Buffett tweet

"America's golden goose of commerce and innovation will continue to lay more and larger eggs. America's social security promises will be honored and perhaps made more generous," he said. "And, yes, America's kids will live far better than their parents did."

