The national health care bill and the nine-month saga that led to its passage swept the country into an emotional and polarizing debate. But even after President Barack Obama signed the bill, many Americans were left to ponder what it all means to them. Here, David A. Rochefort, a Northeastern University political science professor, breaks down the law and its implications.

How will this legislation ultimately affect the average American?
The effects promise to be far-reaching, although it will take time for all of the changes to occur. Among the first groups to benefit will be seniors, due to expanded drug coverage in Medicare, and young adults, who very soon will be able to remain on their parents’ health plans until age 26. Another change this year will be tax credits to help small businesses provide health benefits. Also, private insurers will no longer be able to deny coverage for children with medical problems.

However, it won’t be until 2014 that the law kicks in fully by bringing insurance coverage to an estimated 32 million Americans. For this, necessary measures will include Medicaid expansion, penalties for larger employers who don’t offer health benefits, mandates for uninsured individuals to purchase coverage, and outlawing coverage exclusions for pre-existing medical conditions among all insured. However, the millions of Americans who have and retain good health insurance coverage from their employers will probably not see any substantial change.

Politicians seem to be at odds over whether this law will save money or add to the deficit. What is your take?
Yes, Republicans have complained about insufficient cost containment combined with enhanced coverage and benefits under the new law. The president and his supporters received a major boost when the Congressional Budget Office found the law would dramatically lower the federal deficit over time.

How to resolve this contradiction? Many inefficiencies mark our current health care system, such as the use of costly emergency room services by the uninsured, which will decline as people gain coverage. Future cost control is likely to depend on whether prospective reforms in the law actually bear fruit, and on decisions yet to be made by lawmakers and regulators who oversee the program’s implementation.

What will change in Massachusetts as a result of this national bill?
Massachusetts not only has a law aiming at universal insurance coverage, its program served as a model, in many ways, for the Democrats’ approach. Nonetheless, national health care legislation will lead to some important changes here, including more federal funding for the state’s Medicaid program, a larger number of residents becoming eligible for insurance subsidies and an increase in federal support for the state’s Community Health Centers. New taxes on high-end insurance plans and Medicare payroll tax increases for high-income earners will also eventually affect certain groups in Massachusetts. A discrepancy between national and state law regarding employer and individual non-compliance penalties will need to be straightened out. The federal law has a lesser penalty for those who don’t comply with the individual coverage mandate, and the federal penalty for employers who don’t offer insurance kicks in for companies having 50 or more workers, in comparison with the current state threshold of 11 or more workers.

Will there be enough health care professionals to treat the currently uninsured Americans who will be covered? Will more doctors and nurses be needed?
This is a significant question, one among others that tended to fall below the radar during the debate. The new legislation provides funding for the National Health Service Corps and for increasing Medicaid reimbursements for primary care physicians. It also bolsters family medicine training programs. In the face of concerns about a shortage of active nurses in this country, the law invests in nursing workforce development. Notwithstanding such actions, the supply and distribution of health professionals are likely to remain important issues.