Trump sure likes our clean air and water. I wonder how it got that way.

Among the undisputedly successful social policies of modern American history is the improvement of the environment. Back in the late 1960s, the country was rife with environmental failures: Putrid fire-prone rivers laden with gas and oil. Air so sodden that shirt collars were filthy after a day’s wear. Everyone who worked outdoors in major cities had smoker’s lungs. Lakes were depleted of fish.

I remember those days, having worked in the Council on Environmental Quality in Richard M. Nixon’s White House. We worked closely with Democratic and Republican senators to write the charters of air and water quality. Laws on toxics, waste and drinking water followed. As they took hold, they transformed the environment and health prospects of Americans.

President Trump appears to remember them, too. In his interview Thursday with The Post, he acknowledged our environmental accomplishments, saying “You look at our air and water and it’s now at a record clean.” He contrasted America’s clean environment with the severe pollution in other countries to reassure that the United States is doing fine.

So it makes little sense why, at the same time, the president dismissed the dire scientific consensus on climate change. The clean air and water by no means excuse us from tackling climate change. On the contrary, the droughts and floods and the failing crops and acidic seas — all foreseen by the best minds of scientific agencies and academic institutions — will not only wipe out the nation’s “clean” record that Trump apparently cherishes but also threaten to impoverish and destroy the environment.

Trump doesn’t have to look far for evidence. For more than a week this month, San Francisco was engulfed in smoke so thick that most residents could not see the Golden Gate Bridge. Bicyclists wore masks, schools closed and the city’s air pollution exceeded that in Beijing, all because of a large fire in forests more than 100 miles away. This is what climate change looks like.

But Trump doesn’t “see it,” as he said in the interview. And he added that many other people with "very high levels of intelligence” like himself are not “believers.” He says this even though 13 expert agencies of his own government found — based on 50 or more years of their observations — that changing climate is undeniable and gaining speed.

One stares at the interview transcript waiting for an argument or an authority. A peer-reviewed atmospheric scientist maybe? Has he ordered up a briefing on the science? Consulted his own respected science adviser who is a meteorologist? Referred the question to the National Academy of Sciences? No. The academy and nearly a dozen other national academies have come to the same conclusion.

It’s as if President Franklin D. Roosevelt, on the eve of D-Day, called off the Normandy invasion because he didn’t “see it.” Or President Lyndon B. Johnson, when presented with the completed plan to send a man to the moon, rejected the mission because he wasn’t a “believer.”

The release of the National Climate Assessment is profoundly consequential. Environmental Protection Agency acting administrator Andrew Wheeler has claimed that the report is flawed because it presents a worst-case scenario. (In fact, it offers three models, including projections under business as usual as well as under major reductions in carbon emissions.) Yet researchers would be entirely justified in assuming a continually accelerating trajectory. How could the EPA or any agency charged with protecting public health not assume consequences would be serious?

If there is a way through the fog of denial and indifference, it may be to look for a new priority of adaptation. Policymakers could focus on cooperative efforts to build infrastructure geared toward flood prevention or accelerated research into seeds and plants designed to withstand drought conditions. Perhaps we can expand research into diseases that thrive in high temperatures or neutralize disease-carrying insects likely to proliferate in the coming climate regime. Local leaders might learn from Chicago Mayor Richard M. Daley who in 1997, with the guidance of experts at Chicago universities, planted trees in the city’s parks that could withstand higher temperatures, replaced concrete alleys and sidewalks with permeable pavement and installed reflective roofs.

But a far better scenario would be to have a leader who confronts the realities of science and acts upon it, just as Republicans and Democrats alike did in decades past when faced with what seemed to be insurmountable environmental challenges.

Rejection of the National Climate Assessment carries a grave responsibility. If Trump is wrong — and atmospheric scientists throughout the world believe he is — then his legacy will bear a shameful burden. A planet bereft of leadership will suffer, and historians will note that he was warned.