For anyone who yearns for truly effective health-care reform, last week verged on the nightmarish.

It began when Sen. Joseph Lieberman, the Connecticut independent who caucuses with the Democrats but seems to relish confounding them, flip-flopped on a proposal to let Americans buy into Medicare starting at age 55.

Lieberman voiced support for a Medicare buy-in as recently as three months ago. But when it arose as part of an alternative to the "public option" that he also opposes, he said he was so dead-set against it that he would hold the entire Senate bill hostage.

The week ended with Sen. Robert P. Casey Jr., the antiabortion Pennsylvania Democrat who is also a passionate advocate of changing health care, desperately trying to devise language that might mollify his Nebraska counterpart, Sen. Ben Nelson, another antiabortion Democrat but one who seemed willing to let health-care legislation die if he didn't get what he wanted.

In between, there was an eruption of anger from the progressive end of the Democratic spectrum - the kind that brings to mind the old saying that when liberals form a firing squad, they get in a circle.

The intra-party fight was triggered when former Democratic national chairman Howard Dean, a physician and former Vermont governor, announced that he would rather kill the Senate's health-care bill than go forward.

Whatever Dean's motives, he was quickly seconded by some of the left's more over-the-top voices, such as MSNBC commentator Keith Olbermann. And though Dean softened his stance slightly in a Washington Post op-ed, he still insisted that "as it stands, this bill would do more harm than good to the future of America."

With all due respect, I had to wonder whether he was finally succumbing to an overdose of Ben & Jerry's.

Perhaps Dean has forgotten what it's like to live outside Vermont, one of a handful of states that don't allow insurers to refuse to cover individuals with existing conditions.

Perhaps Olbermann, who announced during one on-air rant that he "self-insures," has forgotten what it's like to live without a TV personality's multimillion-dollar salary.

In the rest of the nation, especially outside the safety net provided by large group plans, millions of Americans still face the worst practices of health insurers - and worry about what might happen if they lose their jobs.

Those who want to seek more fulfilling or productive work, or who dream of starting their own businesses, are limited by the question, "How will I provide my family with reliable health care?" - to their own detriment and at an unknowable cost to the entire U.S. economy.

And the nation's 46 million uninsured, and tens of millions more with Swiss-cheese coverage, live one serious illness away from economic ruin. Or worse: A new study by Harvard researchers estimates that lack of insurance kills about 45,000 people a year.

For all their flaws, the House and Senate bills would go a long way toward fixing this broken system.

That doesn't mean they're perfect, or that devils don't lurk in the details. Several groups warned last week that "wellness incentives" in the latest public version of the Senate bill could undermine one of the legislation's key goals: outlawing price discrimination based on health status.

"It's a huge loophole," Georgetown University health-policy expert Karen Pollitz told me Friday. "Health insurers have been hardwired to discriminate on the basis of health status. That's how they make money."

But as this wrenching debate wears on, here's one thing to remember: Even without the public option or a Medicare buy-in, and for all their shortcomings, the changes on the table in Washington would vastly improve access to health care.

Some of the bills' proposals would take several years to phase in, a favorite complaint from critics, but others would happen right away.

The Senate bill would provide immediate access to coverage for people with existing conditions, with up to $5 billion in premium subsidies. It would help businesses provide coverage to early retirees. It would require group plans that cover dependent children to offer such coverage until they turn 26.

There are so many such ways in which these plans would remake the health-insurance market that it's easy to lose sight of what matters most: that each would move the nation closer to universal coverage than it has ever been, and put changes in place that can be built upon.

"It will set a new floor for consumer protection around health-care issues," Pennsylvania Insurance Commissioner Joel Ario told me Friday.

Ario would have preferred a public option to compete with private insurers, or the Medicare buy-in. At 56, he's worried about how he'll provide coverage for his family at his next job.

But he knows it's tough to get 60 votes for anything in the U.S. Senate. And he's pleased that such a majority may be ready to embrace the basic bargain of this legislation.

The three keys, he says, are to bring everybody into the system by mandating coverage, to bar discrimination against people with health problems, and to subsidize premiums for those who can't afford them. With those three changes, Massachusetts now covers 97 percent of its citizens.

Insurance is about pooling risks as broadly as possible, so few things made Ario madder last week than Olbermann's demand that mandatory coverage be dropped from the Senate proposal.

"Democrats, of all people, should understand that everybody has social responsibility - everybody benefits from being part of the system," Ario says. "If you get sick enough, you're going to be getting care."

Contact columnist Jeff Gelles at 215-854-2776 or jgelles@phillynews.com.