Warren Buffett, the billionaire investor who oversees stakes in some of the largest U.S. banks, said the nation’s lenders have rebuilt capital to the point where they no longer pose a threat to the economy. “The banks will not get this country in trouble, I guarantee it,” Buffett, chairman and chief executive officer of Omaha, Nebraska-based Berkshire Hathaway, said in a phone interview last week. “The capital ratios are huge, the excesses on the asset side have been largely cleared out.” [...] Buffett’s firm has investments in at least four of the seven biggest U.S. lenders by assets, including a stake of more than $14 billion in San Francisco-based Wells Fargo, $5 billion in Bank of America and warrants that allow it to buy $5 billion of Goldman Sachs Group Inc. shares. Berkshire also has a holding in U.S. Bancorp. “Our banking system is in the best shape in recent memory,” Buffett said. [Bloomberg]