Jonathan Alcorn / Bloomberg / Getty Images THEN: In the "70s he devised mortgage-backed securities to shift bank risk to investors, making mortgages more widely available. NOW: He didn't foresee that investment banks would create riskier iterations like collateralized debt obligations (CDOs). "Being one of the founders, it's my problem," he said of the meltdown in 2011. I bear the burden. Next Phil Gramm