The Obama administration used the threat of withholding more bailout money to force out General Motors Corp. chairman and CEO Rick Wagoner, marking one of the most dramatic government interventions in private industry since the economic crisis began last year. In wrestling with the economic crisis, the government has demanded the ouster of the head of American International Group Inc., but only as it took a majority shareholder position. In this case, the administration has ousted a major CEO as part of an ongoing restructuring. The move also indicates that the Treasury Department intends to wade more deeply than most observers expected into the affairs of the country's largest and oldest car company.