Sea change. An enormous one. That’s the only way to understand President Trump’s first 100 days — as a breaking from and often a breaking of the Obama presidency, one every bit as turbulent as what’s encountered by a sailing ship going from calm seas into a hurricane.

Trump’s first 50 days were a jumble of ups and downs, mostly downs. But beginning with the flawless testimony of Neil M. Gorsuch to the Senate Judiciary Committee and his subsequent confirmation under rules that will speed the way for future Supreme Court nominees, the Trump turnaround began and gained an almost uninterrupted momentum. The president’s directive to strike Syria after it apparently rained sarin poison on babies and toddlers was a defining moment, reinforced by using the “mother of all bombs” in Afghanistan and dispatching an armada of weaponry toward North Korea (no matter how indirect a route the ships took to arrive there).

All along, a legislative legacy was passing beneath the noses of Manhattan-Beltway media elites who could not be bothered to learn the wide-ranging implications of the baker’s dozen of Congressional Review Act measures that passed the House and Senate by simple majorities and were signed into law by Easter. This is a legislative outpouring not exceeded in substantive impact by any modern president except Franklin Roosevelt, though others have seen more statutes passed. Yet because regulatory rollback bores or confounds journalists, these new laws were discounted or simply dismissed.

In fact, a law passed under the little-used Congressional Review Act not only repeals an existing regulation but also bars the affected agency from acting in the same area without explicit legislative approval. These measures will therefore reverberate for decades, whether by hamstringing public funding of abortion at the state level; narrowing the reach of environmental regulators over “waters of the United States ”; or slapping down the U.S. Fish and Wildlife Service on hunting in Alaska.

Trump’s Cabinet appointees, meanwhile, represent the most conservative collection of the modern era, and his national security team 2.0 (with H.R. McMaster taking the place of Michael Flynn as national security adviser) is at least the equal of any that has served since the end of the Cold War. Trump’s sometimes loose campaign rhetoric on national security has been realigned with governing realities, underscored by assessments of how badly damaged the past eight years left the country. President Barack Obama’s legacy is easily summarized in eight words: “leading from behind,” “red line,” “JV ,” Aleppo and Libya.

Sure, there have been big fumbles and stumbles, especially at the start: the first executive order on immigration; the use of “so-called” in referring to a federal judge (never appropriate or prudent); branding journalists, no matter how biased, the “enemy of the American people.”

Of continuing concern are the administration’s refusal to release White House visitor logs, West Wing staff intrigues and the glacial pace of appointments, particularly the absence of Republicans at the Pentagon and the failure to move swiftly on filling appellate court vacancies. All these are unforced errors that have combined to deny Trump the accolades that would have been forthcoming had his accomplishments not been so interlaced with pratfalls.

Trump’s most significant setback — the collapse of the repeal and replacement of Obamacare — is not yet a conclusive defeat. And a spate of executive orders has set the stage for regulatory relief across the federal government. Could Trump have done better? Of course. But what he has done is without question of historic and lasting impact.

On the political front, there is the slight but ongoing shuffle to the center — a very good thing so long as the judicial picks remain originalists and the military rebuilding robust. In office, Obama moved left, left and then more to the left. Trump has begun his presidency by casting off his moorings to the hard right while keeping true believers such as Attorney General Jeff Sessions in the forefront and the rhetoric of jobs, jobs, jobs constantly resounding.

This a politically potent combination, and the drop-off in protest marchers between the Jan. 21 and April 15 rallies and the disappointments to Democrats in the Kansas and so far Georgia special elections — Jon Ossoff’s best shot at actually winning Georgia’s 6th Congressional District seems to have come and gone — telegraph that it is working. Progressives’ complaints are increasing both in number and decibels, and their energy veering wildly leftward, much to the delight of Republicans who worry about the downside potential of November 2018.

Trump has been adapting and learning in his own, always unique and often far-too-unnecessarily-divisive way. Just imagine what the next three and two-thirds years can bring — if he minimizes the errors of the first 100 days and repeats the parts that have been greeted with broad-based conservative applause.