The health care drama in the U.S. Senate is cresting. After months of hearings--and decades of dithering--it is time to see if the United States is going to remain the only advanced industrial nation in the world that does not provide universal health care.

Some have compared the role played by Senator Snowe to that of Senator Everett Dirksen from Illinois, who lined up Republican support for the Civil Rights Act of 1964. But that would be overstating the case. Senator Snowe appears to be driven by personal conviction with little support within her party. It will be interesting to watch her forthcoming votes to gauge how far she is willing to break with party ranks. Will she support a public option? If so, with what conditions?

The health care debate shows in full the Senate's anti-majoritarian tendencies. Democratic senators hold 60 votes (out of 100), yet so far they have struggled to fashion legislation because they fear a filibuster, which allows a mere 41 senators to stymie what the majority wants.

The 40 Republican senators represent barely a third of all Americans. If a single Democrat is added to a G.O.P. filibuster, they can torpedo what two-thirds of the nation wants. It's the most blatant form of minority rule. Only 16 senators are women and five are racial minorities. With two senators elected per state regardless of population, the Senate is the most unrepresentative body outside Britain's House of Lords. But at least Britain has the sense not to allow the Lords to vote on important legislation.

Senators representing a small segment of the nation have thwarted not only health care reform but also renewable energy policy, sensible automobile mileage standards, cuts in subsidies for oil companies, tougher campaign finance reform, Congressional oversight of national security and war, and more.

So the credibility of the entire Senate is on the line. Senator Snowe may wield a pivotal vote on health care, but it is in a body that is unrepresentative and anti-majoritarian by design. How long are we Americans going to ignore this constitutional defect?