The Obama administration’s signature legislation, the Affordable Care Act (ACA), passed in 2010 and launched a massive, multiyear phase in process of policies and plans.  This is the biggest change in the nation’s health insurance system since the establishment of Medicare nearly a half-century ago.  Finally Americans can buy insurance regardless of their health history or employment status.

As a result of the 2010 elections, the Republicans gained control of the House of Representatives.  Since then the party has obsessively concentrated on repealing, defunding, or delaying ACA.   House Republicans have voted more than 40 times to obstruct the law, only to be blocked by the Democratic-controlled Senate.

The Republicans’ most recent assaults amount to extortion.  The party ties the continuing funding of the government to eliminating funding for or postponing implementation of the ACA.  Meanwhile, President Obama and Senate Democrats call for a straight forward vote on government funding free of any entangling stipulations.

The bitter budget impasse has resulted in a partial government shutdown that began on October 1.  Social Security checks will still go out, and many transportation and security personnel remain at their posts.  On the other hand, the damage includes shuttered national parks, unpaid furloughs for 800,000 federal employees, and a range of government services no longer available.  Ironically, the shutdown has virtually no impact on ACA.

Even with the government now in partial shutdown, a much more catastrophic event looms.  By not lifting the debt ceiling, the government would, for the first time, be unable to pay its bills beginning on October 17.  A debt default would likely drive the national economy back into a recession and roil the global economy.

The ACA requires the creation in every state of new health insurance exchanges where people can shop for health plans.  Misinformation about the law and its sheer complexity has caused confusion and skepticism.  But trained “navigators” help people understand it.

Open enrollment in the exchanges which also began on October l makes it possible for millions of uninsured people who can’t get or can’t afford health insurance to obtain coverage with the aid of government subsidies.  There will also be tax incentives for small businesses to offer employees insurance.

The ACA intends to help low income people by dramatically expanding Medicaid eligibility to all people up to 138 percent of the poverty line.  But about half of the states largely controlled by Republicans declined to participate in the expansion leaving millions of poor people uncovered.

The Act makes it illegal to deny coverage because of pre-existing health conditions.  It allows young adults to stay on their parents’ health insurance policy until age 26.  It prevents insurance companies from imposing lifetime limits on coverage and phases out annual limits on coverage.

The law requires insurance companies to provide free preventive care and annual health exams.  Under the act, health care plans will include coverage for prescription drugs, maternity care, and mental health care.  And insurers must spend it least 80 percent of premiums on medical care.

Some of us wanted Medicare for all or at least a public option.  Still the ACA significantly expands the existing health care system.  It represents a truly historic journey toward near-universal health care.  It is modeled on the one in Massachusetts which covers 97 percent of the population and receives an 84 percent approval rating.

The ACA clearly is imperfect; it has dozens of complicated, interlocking parts; and there have been glitches and problems.  Yet subsidized coverage expansion and restrictions on insurance company abuses constitute a great achievement.  In the end, the ACA reforms represent a much fairer way of delivering health care.