The specter of President Carter has suddenly emerged from the 1970s to haunt the Trump administration.

A Wall Street Journal editorial warns Trump that “on present course his Presidency is careening toward a historic reputation where names like Jimmy Carter and Richard Nixon reside.”

The New York Times, meanwhile, published an op-ed by Matthew Continetti extending the Trump-Carter comparison. “Neither president had much governing experience before assuming office,” Mr. Continetti writes. “Like Mr. Carter, Mr. Trump was carried to the White House on winds of change he did not fully understand. Members of their own parties viewed both men suspiciously, and both relied on their families. Neither president, nor their inner circles, meshed with the tastemakers of Washington. And each was reactive, hampered by events he did not control.”

The Journal is correct that Mr. Carter suffers from a poor reputation, and Mr. Continetti is correct to surmise that Mr. Trump would want to avoid Mr. Carter’s political fate of failing to win re-election.

I’m a lifelong admirer of Ronald Reagan, who defeated President Carter in the 1980 election. I’ve also got strong differences with Mr. Carter when it comes to Israel and the Palestinian Arabs. But even I can see, with the perspective of history, that the Carter presidency is underestimated.

Consider that President Carter chose as chairman of the Federal Reserve Bank Paul Volcker, whose interest rate increases eventually succeeded, under Reagan, in reining in inflation.

Remember that Mr. Carter signed into law (albeit reluctantly) the Steiger Amendment, named for a Republican of Wisconsin, William Steiger. That cut the capital gains tax to 28% from the effective rate of 49.875%, to which it had been increased under Nixon and Ford.

Recall that Mr. Carter worked with Congress to pass the Airline Deregulation Act of 1978, which led to lower fares, the abolition of the Civil Aeronautics Board, and the rise of discount carriers like People Express and Southwest. He also passed the Motor Carrier Act of 1980, deregulating trucking. Air cargo, railroad freight, even to some extent banking and energy saw bureaucracy rolled back during the Carter years, paving the way for the growth of FedEx and alternative energy.

The deregulation, by the way, was done by President Carter in concert with an aide to Senator Edward Kennedy, Stephen Breyer, who eventually became a Supreme Court justice. A Cornell University professor, Alfred Kahn, also played an important role. It’s a story well told in Nick Gillespie’s and Matt Welch’s book “The Declaration of Independents.”

In October 1978, President Carter asked a rally, “Do you want a government that will get the regulatory agencies’ and government agencies’ nose out of the private sector’s business and let our free enterprise system work in the United States? Well, that’s the kind of government we’re trying to bring you in Washington.”

Even on foreign policy, where the failed Iran hostage rescue mission symbolized Carter’s impotence, there were bright spots, including the 1978 Camp David Accords between Israel and Egypt.

What does all this mean for Mr. Trump?

Perhaps simply that being unpopular with “the tastemakers of Washington” needn’t necessarily translate into a presidency without enduring, admirable, and even historic accomplishments.

If Mr. Trump can, like Mr. Carter, cut capital gains tax rates, roll back regulation, guard against inflation, and seize peacemaking opportunities when they are genuinely available, as they were in the case of Anwar Sadat and Menachem Begin, then historians 40 years from now will be singing his praises, or at least remembering his achievements.

One lesson of the post-Reagan era is to start with low expectations of politicians. Then you’ll be pleasantly surprised rather than deeply disappointed. If President Trump manages to accomplish what President Carter was able to, a lot of people would probably happily call it a success. Given declining standards and depending on what the alternatives are, such a performance might even be enough, these days, to merit re-election.