The political impact of Thursday’s stunning Supreme Court decision on health-care reform is clear — good for President Obama and the Democrats, bad for Mitt Romney and the Republicans — but fleeting, and thus secondary. Much more important is what the ruling means in the long term for the physical and moral health of the nation.

All but lost in the commentary about the court’s 5 to 4 ruling, with Chief Justice John G. Roberts Jr. unexpectedly joining the majority, is that the Affordable Care Act was intended as just a beginning. We have far to go, but at least we’re on our way.

Obama’s great achievement is not any one element of the health-care reform law — not even the now-upheld “individual mandate,” which compels individuals to have health insurance or pay a fine. The important thing is the law’s underlying assumption that every American, rich or poor, should have access to adequate health care.

In the rest of the industrialized world, this simple idea is taken for granted. When Obama took office, however, about 50 million Americans lacked health insurance. Many low-income families, especially the “working poor” who make too much money to qualify for Medicaid, were faced with impossible decisions: Take a sick child to the doctor or pay the rent? Buy medicine or buy groceries?

Those who cannot afford health insurance do ultimately receive care, of course — but often in hospital emergency rooms, where treatment is much more expensive than in a doctor’s office. Our system is thus both callous and extravagant, costing much more than it should while delivering substandard results.

The World Health Organization gives the U.S. health system an overall ranking of 37th in the world, far below other Western democracies. The CIA World Factbook — hardly the work of a bunch of left-leaning one-worlders — reports that life expectancy in the United States is not just lower than in other industrialized countries but also lower than in Jordan and Bosnia.Infant mortality in this country, according to the CIA, exceeds that of Slovenia and Cuba. It is possible to quibble with these figures but not to ignore them. We should be ashamed of ourselves.

Most working-age Americans who have health insurance obtained it through their employers. But this is a haphazard and inefficient delivery route that puts U.S. businesses at a disadvantage against foreign competitors, most of which shoulder no such burden. Tying health insurance to the workplace also distorts the labor market and discourages entrepreneurship by forcing some employees to stay where they are — even in dead-end jobs — rather than give up health insurance.

For healthy individuals, it is crushingly expensive to buy insurance on the free market. For those with preexisting medical conditions, it is essentially impossible — but not for long, thanks to the Supreme Court’s landmark ruling.

Rather than seek a radical reshaping of the health-care system, Obama pushed through a set of relatively modest reforms that will expand insurance coverage to a large number of the uninsured — about 30 million — but still not all. He also tried to use free-market forces to “bend the curve” of rising costs, slowing but not halting their rise.

The result — the Patient Protection and Affordable Care Act — is a huge, complicated, unwieldy piece of legislation. I would have loved to see the president try for something simpler and more elegant, perhaps a “Medicare for everyone,” single-payer system. Maybe that’s where we’ll end up someday.

But despite all the rhetoric we’ll hear from Romney and the GOP until Election Day, health-care reform is here to stay. Provisions such as guaranteeing insurance coverage to those with preexisting conditions are too consumer-friendly to be taken away, and once these measures take effect, which happens in 2014, insurance rates would rise sharply — and unacceptably — without the individual mandate.

And medical costs will continue to soar, despite the law’s efforts to contain them. Inevitably, if only because of deficits and the national debt, Congress will have to revisit the health-care issue with an eye toward more radical changes.

When that next big push takes place, it will be with the underlying assumption that health care should be available to all who need it regardless of their ability to pay — that it is not a privilege but a right. Progressive presidents since Theodore Roosevelt have tried to enshrine this principle. Barack Obama did it.

eugenerobinson@washpost.com