One year ago this week, President Barack Obama signed the Patient Protection and Affordable Care Act into law, ensuring quality, affordable health coverage to all Americans, cracking down on the worst abuses by health insurance companies and placing a new emphasis on wellness and disease prevention.

Yet today, there is a misguided effort to repeal the law. The fight to provide access to quality, affordable health care for all has only just begun.

The good news is that this time around, the debate dynamics have shifted. As people learn more about the long-overdue reforms in the Affordable Care Act — including benefits and consumer protections now guaranteed by law — support for health care reform is growing steadily.

A year ago, we were bogged down in the messy, frustrating politics of passing the bill. Now, what’s at stake is crystal clear: Are we going to put health insurance companies back in the driver’s seat to discriminate based on pre-existing conditions and return to the abuses and discriminatory practices of the past? Are we going to revoke access to health insurance for more than 30 million Americans? Are we going to add hundreds of billions of dollars to the deficit by wiping out the savings in the Affordable Care Act?

The nonpartisan Congressional Budget Office estimates the law will reduce the deficit by $210 billion in the first decade and by more than $1 trillion in the second decade.

The law’s jewel in the crown is ending denial of coverage due to pre-existing conditions. It is a sobering fact that nearly half of non-elderly Americans have some type of pre-existing condition — like high blood pressure, arthritis or heart disease.

Similarly, the law bans the outrageous practice of canceling policies when people get sick. Gone are the days when the largest health insurer in California could use technicalities to cancel the policies of women who get breast cancer.

The law also prohibits insurers from imposing lifetime limits on benefits, and it allows parents to keep their children on their policies until age 26.

Americans will not allow these hard-earned protections and benefits to be taken away.

Conservatives attack the provision of the law requiring people to purchase health insurance. They claim it is an “assault on freedom.” Well, it is an assault on freedom for people to go without insurance, seek treatment in emergency rooms and stick other Americans with their health care bills. Uncompensated health care adds an estimated $1,100 a year to every family’s health insurance premiums.

The individual mandate is just common sense — that’s why so many Republicans supported it in the past. Indeed, as governor of Massachusetts, Mitt Romney put an individual mandate at the center of his state’s health reform law. By eliminating free riders and putting everyone in the risk pool, we keep rates down for everyone. This is the only way people with pre-existing conditions are not denied affordable coverage.

When we join together, we have more freedom. When everyone is covered and no one is left out, we enhance liberty. Health reform is all about freedom. Freedom from the fear that if you get sick, you won’t be able to afford a doctor. Freedom from the fear that a major illness will lead to financial ruin. These are the practical freedoms that matter to Americans.

With this landmark law, we are beginning to replace the current sick care system with a genuine health care system — focused on wellness and prevention. We are beginning to reward health care providers for the quality of care they provide, not just the quantity.

The Affordable Care Act is not perfect. It is not like the “Ten Commandments,” chiseled in stone. It’s more like a starter home — suitable for improvement.

I look forward to working with my colleagues to make sensible changes as we continue to implement the law. I invite them to bring their tool kits, rather than their sledgehammers, so we can work together to improve the law.

The choice is to go forward or be dragged backward. The great majority of people want to go forward to build a reformed health care system that works not only for the healthy and wealthy — but for all Americans.