Before the oral arguments in late March, the vast majority of legal scholars felt confident that the Supreme Court of the United States would uphold the individual mandate against the constitutional challenge that 26 states have levied against it. Since the oral arguments, that confidence has been severely shaken. This article asks why legal scholars were so confident before the argument and what has made us so concerned since the argument. The article posits that certain fundamental characteristics of health insurance, particularly its unusual role in steering health-care consumption decisions, which distinguishes health insurance from standard kinds of indemnity insurance, should make the constitutional question easy, but the Obama Administration’s legal team was understandably hesitant to highlight those unique characteristics in its arguments. Because the Supreme Court justices seemed not to understand the uniqueness of health insurance without the government’s help and because the justices seemed unusually willing to adopt a new constitutional constraint in this case, the individual mandate appears to be in far greater jeopardy than we legal scholars anticipated.