While the XM-Sirius merger is worth either $5 billion or $13 billion, the sale of radio giant Clear Channel to a pair of private equity firms is worth $19.5 billion. Or it would be, if the banks handling the sale don’t pull out, as they’re threatening to do. If banks like Citigroup, Deutsche Bank, and Morgan Stanley do pull out, Clear Channel, and Bain Capital and Thomas H. Lee Partners, are threatening to sue to force them to complete this ridiculously enormous transaction. That mortgage market crumbling is their problem.