Once again the world economy has proved the naysayers wrong and there's been a "real rebound" so far this year, Barclays CEO Robert Diamond told CNBC Wednesday. "One of the lessons we’ve learned in the last couple of years is every time it’s doom and gloom ... the economy is far more resilient," he said. "We see China at 8 percent to 9 percent growth, and reduction in unemployment [cnbc explains] in the U.S. So we’ve seen a real rebound." That even extends to Europe, which was stabilized by the European Central Bank's [cnbc explains] second liquidity injection. President Mario...