Do you remember the debates over the Affordable Care Act, aka ObamaCare? Now that repeal of the law has become a major campaign issue, it may be helpful to remember why Congress passed it in the first place.

Early in 2010, as the climactic votes neared, a parade of the legislation's defenders—from the House, Senate and Obama administration—appeared across the media. All had the same message: pre-existing conditions. They named the names of families "victimized" by companies that had refused to sell...