WASHINGTON — Is it safe to say that Barack Obama’s presidency will be remembered as the most consequential since Ronald Reagan’s — a presidency that “changed the trajectory of America” and “put us on a fundamentally different path”?

That was the audacious goal Obama set for himself during his 2008 campaign. Now is a useful time to assess his progress because the sixth year of any president’s tenure tends to be seen as a low point. Familiarity breeds impatience and frustration — among commentators, at least, whose narrow focus on which party is perceived as “winning” the day or the week misses the bigger picture.

In both the domestic and foreign spheres, Obama has had transformational impact. And there is more to come.

Reagan’s great achievement at home was to shift the political spectrum to the right. People tend to forget how radical his ideas once seemed. Tax cuts and massive deregulation were somehow going to produce more revenue? Wealth would inevitably trickle down and benefit the middle class and even the poor? It was not a Democrat but a fellow Republican, George H.W. Bush, who mocked the whole concept as “voodoo economics.”

That’s what I’d still call Reagan’s program, but he altered the political debate to such an extent that what once were fringe ideas came to be seen as centrist. By the time Obama took office, the combination of Reaganite policies — taken to extremes the Gipper might never have contemplated — and globalization had produced a nation where the rich were becoming obscenely rich and everyone else was struggling to tread water.

Obama’s impact has been to bring the words “fairness” and “equality” back into the political lexicon.

His biggest legislative accomplishment, the Affordable Care Act, is a landmark because it establishes the principle that health care should be considered a right, not a privilege. Democrats such as Harry Truman — and Republicans such as Richard Nixon — sought for decades to move the nation toward universal care. The fact that Obama succeeded where others failed is, in itself, a huge achievement.

Perhaps as important, however, is the fact that while Republicans still claim they want to repeal Obamacare, the debate within the party centers on how best to expand health insurance coverage. Returning to the way things were before the ACA is not an option.

Health care is part of a larger suite of issues on which Obama has swung the pendulum back to the left. He made the case, for example, that more regulation of the financial sector was needed. Republicans were forced to give way. The president has been hammering away in speeches about the need for an increase in the minimum wage. Republicans haven’t caved on this yet, but in the end they almost surely will, because of widespread public support for it.

Whether or not Democrats lose the Senate, Obama will have a tough time getting significant legislation passed in his final two years. Please don’t tell me he simply needs to be a better politician, like Bill Clinton. Obama ran rings around both Clintons in 2008. A black man with the middle name of Hussein who gets elected president twice should be in the all-time-all-world Politics Hall of Fame.

But he can still have transformational impact. Working through the Environmental Protection Agency, Obama can take major steps to limit carbon emissions. I don’t know if he’ll go as far as I believe he should, but whatever he does will be, by definition, a big deal.

In foreign policy, Reagan applied pressure to the weak points of the Soviet empire and helped break it apart. Obama has taken on an equally big and important task: redefining the U.S. role in a vastly changed world.

Obama is not the first president to endorse multilateralism but he may be the first to mean it. He agreed to use force in Libya only after France and Britain nominally took the lead. He has kept the NATO allies together in cautiously dealing with the Ukraine crisis. He has refused to be drawn into Syria because he is unsure whether intervention would make the situation better or worse.

The president realizes that even the most powerful nation on earth cannot mediate every dispute, take sides in all wars, alleviate all suffering. He acknowledges our limitations and more narrowly defines our national interest. The public approves, even if some foreign policy sages are apoplectic.

Obama can be reserved and introspective. Usually, however, I find him energized, confident, determined — and fully aware that he is shifting the ground.

Eugene Robinson is a Washington Post columnist. His email address is eugenerobinson@washpost.com.