It wasn’t a surprise when President Obama tapped Joshua Gotbaum in November 2009 to head the Pension Benefit Guaranty Corp., which insures U.S. private sector pensions. The son of longtime labor union leader Victor Gotbaum began serving Democratic presidents during the Carter administration in the late 1970s. But the Harvard Law School grad has also devoted decades to corporate mergers and acquisitions, workouts and restructurings. Gotbaum’s new role has allowed him to bring the two sides of his career together to improve pensions at U.S. corporations. He has become a national voice calling for new forms....