The decision was a striking
victory for the president and Congressional Democrats, with a majority, including
the conservative chief justice, John G. Roberts Jr., affirming the central
legislative pillar of Mr. Obama's term.
Many observers called the case
the most significant before the court since at least the 2000 Bush v. Gore
ruling, which decided a presidential election. In addition to the political
reverberations, the case helps set the rules for one of the largest and
fastest-growing sectors of the economy, one that affects nearly everyone from
cradle to grave.