Now , instead of moving back down the insurance food chain where the rest of us suffer -- I have some dependent health insurance claims I 'd love to see paid -- Mr. Spitzer has cast his eyes on the very summit : On April 11 , he and other financial regulators will be questioning the Wizard of Omaha , Warren Buffett , about possible financial manipulation at several giant international insurance companies , including American International Group and General Re , a subsidiary of Mr. Buffett 's Berkshire Hathaway .