As the worsening economy leads to massive job losses—potentially forcing millions more Americans to go without health insurance—FRONTLINE travels the country examining the nation's broken health care system and explores the need for a fundamental overhaul. Veteran FRONTLINE producer Jon Palfreman dissects the private insurance system, a system that not only fails to cover 46 million Americans but also leaves millions more underinsured and at risk of bankruptcy.

At its best, American health care can be very good. For Microsoft employee Mark Murray and his wife, Melinda, their employee health plan paid for eight years of fertility treatments and covered all the costs of a very complicated pregnancy. "If it wasn't for our health insurance," Murray says, "we wouldn't have a baby boy right now." The Murrays' medical bills totaled between $500,000 and $1 million, and their plan covered every penny.

But beyond large, high-wage employers like Microsoft, FRONTLINE learns that available, affordable, adequate insurance is becoming hard to find. Small businesses face a very bleak outlook for finding and keeping coverage. Coverage is becoming more expensive and less comprehensive, with high deductibles, co-pays and coverage limits. Georgetown University Research Professor Karen Pollitz explains that for many people, the current system is "like having an airbag in your car that's made out of tissue paper: I'm so glad that it's there, but if I ever get in a crash, it's not going to protect me."

Outside of employer-based health care plans, matters are even worse. Americans seeking insurance in the individual market must submit to "medical underwriting," and if they have a pre-existing condition, they will likely be denied. Kaiser Permanente Chairman and CEO George Halverson says frankly: "I could not get insurance. I've had heart surgery, and so I am completely uninsurable in the private market. So it's important that I keep my job."

Across the U.S., FRONTLINE finds people making life decisions based on health insurance, stuck in jobs because of so-called job lock. One such person is 23-year-old Twin Cities, Minn., resident Matt Johnson, who put his career dreams on hold to get a job at Menards home improvement store because its benefits package covers his ulcerative colitis. Americans even stay in bad marriages, says Pollitz, "because they just can't afford to divorce their health insurance."

For those Americans who find health coverage in the private market, there's no guarantee it will protect them. In 2007, Palm Desert, Calif., realtor Jennifer Thompson received a letter from Blue Cross accepting her for coverage that read: "Congratulations! You have been approved for coverage with Blue Cross of California. ... The immediate value of your coverage is peace of mind." But then Thompson discovered she had a cancer that required surgery, and three days after leaving the hospital, she received a letter from Blue Cross saying that her insurance was "rescinded," leaving her uninsured and owing more than $160,000 in medical bills. Blue Cross cited Thompson's previous history of cancer and results from a recent doctor's visit as the reasons for the rescission. "Our system is not working," says Professor Pollitz. "It's designed to cut out on you right when you need it the most." When questioned about Thompson's case, Sam Nussbaum, chief medical officer of WellPoint, which owns Blue Cross of California, told FRONTLINE that because of legal considerations, "I can't speak to that circumstance ... but no one likes to see a situation like this. People are buying health security."

In the past, some states required insurance companies to cover everyone but found that many people waited to buy insurance until they fell ill, causing "adverse selection," or a higher ratio of unhealthy to healthy people in the insurance pool. As a result, insurance companies stopped doing business in those states. Today, only five states—New York, New Jersey, Massachusetts, Maine and Vermont—guarantee everyone insurance, a "privilege" reflected in premiums. "If we look at the average premium of those states," says WellPoint's Nussbaum, "that premium is three times higher on average—maybe $600 to $700 versus a [state] where the insurance market has allowed medical underwriting."

For some Americans, life becomes a quest to find and keep health insurance. In 1994, Nikki White, a Bristol, Tenn., native with dreams of becoming a doctor, was diagnosed with lupus, a serious but treatable autoimmune disorder. Too ill to work, she lost her health insurance for several years, but then received coverage from the state's Medicaid program. Soon, budget cuts made her ineligible for the state program. A few months later, White was rushed to the ER with severe lupus complications and racked up nearly $1 million in medical bills. She finally secured insurance under the government HIPPA law, but her condition was too advanced, and in 2006, at the age of 32, she died. White's primary care physician, Amylyn Crawford, tells FRONTLINE: "Nikki didn't die from lupus. Nikki died secondary to the complications of a failing health care system."

Around the world, other developed democracies offer universal health care, requiring insurance companies to cover everyone. People are mandated to buy it; insurance for the poor is subsidized; and governments control prices by setting the cost of everything from doctors' salaries and hospital rooms to drugs and MRIs. But efforts to implement similar policies in the U.S. have proven unsuccessful. In 2006, Massachusetts implemented reforms mandating everyone be covered by health insurance, but there are still problems of affordability. FRONTLINE profiles the Abramses, a Massachusetts family of four earning $63,000 annually, who found that although they were too prosperous to receive a health care subsidy, they could not afford to buy a health care insurance policy at around $12,000 a year. "What we're finding out in Massachusetts," says veteran insurance industry executive and consultant Robert Laszewski, "you can mandate that people have health insurance, but if it costs more than they can afford, it doesn't matter."

As President Obama launches his plan for reforming health care, Kaiser Family Foundation President Drew Altman tells FRONTLINE: "This is the first big opportunity for health reform since ... [the] early 1990s. And a question is again, pointedly, whether we will blow the opportunity again this time or [whether] we will actually get it all done or get something significant done." But consultant Laszewski wonders if Americans have the will to make it happen. "Every doctor I meet says he's underpaid. I've yet to meet a hospital executive who thinks he or she can operate on less. I have yet to meet a patient who is willing to sacrifice care. So we have this $2.2 trillion system, and I haven't met anybody in any of the stakeholders that's willing to take less. And until we're willing to have that conversation, we're just sort of nibbling around the edges."