This week, President Barack Obama laid it on the line: Not only does he want health care reform, he wants it now. And he gave Congress its marching orders: Pass the bill for his signature before the Easter recess, or say goodbye to their party's signature piece of legislation as well as one of the most important pieces of social legislation in many decades. We are on the cusp of an historic moment.

Obama's demand is a tall order, though doable. In essence, it means the House of Representatives must pass the current Senate health care reform bill, passed last December in the Senate with a 60-vote super-majority. If the House passes the Senate bill, it will go directly to the White House for the president's signature, at which point health care reform becomes the law of the land, one of the most significant pieces of legislation since passage of the Social Security Act in 1935.

But in order for the House to approve the Senate bill, which is considerably more conservative than the House version, the House is going to insist on a number of changes. These changes will go the Senate for approval only after the president has signed the bill into law. The Senate will consider the changes under a parliamentary procedure called "reconciliation," enacting legislation that requires only 51 Senate votes, thus avoiding a prolonged filibuster. Republicans are crying "foul," though they themselves have used reconciliation many times in the past to pass legislation they considered to be too important to risk a filibuster. These included the enormous Bush tax cuts that have done so much damage to the economy.

But House approval of the Senate bill is by no means assured, as there are a number of House Democrats who don't trust their Democratic colleagues in the Senate to follow through. First, liberal Democrats don't like the restrictions on abortion in the Senate bill, while moderate and conservative Democrats want to see even more restrictions. Second, centrist Democrats are afraid the bill is simply too expensive for the country to accept in its present mood, and there will be serious consequences at the polls in this November's congressional elections. Moreover, it is the Senate parliamentarian who decides which bills can be passed under the reconciliation procedure, a procedure reserved for financial matters. Can the House's requested changes be accommodated under the rules decided by the Senate parliamentarian? These are matter now under intense discussion between Speaker of the House Nancy Pelosi and members of the Democratic caucus. Pelosi cobbled together the House bill last year, a task once thought to be impossible, and she is now confronted with another enormous challenge.

The president is taking a huge political risk, though undoubtedly he, Speaker Pelosi and other Democratic leaders have concluded that at the end of the day there will be enough House votes to pass the Senate bill. I suspect Republican leaders have reached the same conclusion, hence their outrage as well as promises to revoke health care reform if they regain control of the House and Senate. Whatever the outcome, it is almost certain to be close.

Various polls indicate that most Americans are wary of current health care reform legislation, if not actually opposed. On the other hand, other polls show that a considerable majority of Americans approve various aspects of current legislation, like preventing insurance companies from refusing insurance to those Americans with pre-existing conditions. Undoubtedly, the president is betting that public opinion will swing in his favor once health care reform is passed and people grasp the reality of what has happened. He is taking a huge and calculated risk, but I suspect he is right.

Obama cast his demand for action in the larger context of doing what is right and not what is politically popular or expedient. Again, I think he has got it right. Obama is in command of a very complex issue. Giving the public what it wants at any given moment for the sake of popularity is to fail the nation. Giving the nation what it really wants is to give it leadership at a time of crisis. Ultimately, popularity rests upon respect. The public knows that, even if it doesn't always agree with every presidential decision. What it does want above all, is firm leadership. This is what Obama demonstrated this week.

In my view, health care reform is as much a moral issue as it is a financial one; providing universal health care, in whatever form we choose to make it, helps to define us as a nation.

William M. Stewart, a former U.S. Foreign Service officer and Time magazine correspondent, lives in Santa Fe. He writes weekly on foreign affairs.