The health-care case wasn't about broccoli or the Commerce Clause. It was about ratifying a change in our nation's social policy.
In civics class we learn that federal courts decide whether laws passed by Congress and the state legislatures are constitutional. Therefore the federal courts are the guardians of our Constitution. That is certainly true, but it not the whole story. In fact, the most important function of the federal courts is to legitimate state building by the political branches. That is the best way to understand what happened in the Health Care Case. It also helps explain why Chief Justice John Roberts' opinion is written the way it is.
What is "state building?" Throughout our country's history, government has taken on many new functions. The early 19th century American state actually didn't do very much more than national defense and customs collection. The executive branch was tiny. Over the years, the federal government took on more and more obligations, offering new protections and new services for its citizens. After the Civil War, Congress passed a series of civil rights laws, it created the Interstate Commerce Commission to regulate railroads, it passed an income tax, and early in the twentieth century it created a central bank. State building really took off after the New Deal, which established the modern administrative and regulatory state and added a host of labor and consumer protection regulations, investments in infrastructure, and Social Security. The National Security State was born after World War II, and the 1960s brought new civil rights laws and new social welfare programs through the Great Society. At the turn of the 21st century, the federal government expanded its national security infrastructure even further, implementing vast new surveillance programs and strategies for dealing with terrorism-- including detention of "enemy combatants" -- that I collectively call the National Surveillance State.
Whenever the federal government expands its capabilities, it changes the nature of the social compact. Sometimes the changes are small, but sometimes, as in the New Deal or the civil rights era, the changes are big. And when the changes are big, courts are called on to legitimate the changes and ensure that they are consistent with our ancient Constitution. In this way, courts ratify significant revisions to the American social contract.