A “scram” is the emergency shutdown of a nuclear power plant. Control rods, usually boron, are dropped into the reactor and these absorb the neutron flux and shut it down.

President Trump, a supporter of nuclear power, has in a few words scrammed the whole nuclear industry, or at least dealt its orderly operation a severe blow.

Scientists see nuclear waste as a de minimus problem. Nuclear power opponents — who really can’t be called environmentalists anymore — see it as a club with which to beat nuclear and stop its development.

The feeling that nuclear waste is an insoluble problem has seeped into the public consciousness. People, who otherwise would be nuclear supporters, ask, “Ah, but what about the waste?”

For its part, the nuclear industry has looked to the government to honor its promise to take care of the waste, which it made at the beginning of the nuclear age.

In the early days of civilian nuclear power — with the startup of the Shippingport Atomic Power Station in Pennsylvania in 1957 — the presiding theory was that waste wasn’t a problem: It would be put somewhere safe, and that would be that.

Civilian waste would be reprocessed, recovering useful material like uranium and isolating waste products, which would need special storage. The most worrisome nuclear byproducts are gamma, beta and X-ray emitters, which decay in about 300 years.

The long-lived alpha emitters, principally plutonium, must be put somewhere safe for all time. Plutonium has a half-life of 240,000 years. It’s pretty benign except that it’s an important component of nuclear weapons.

If you get it in your lungs, you’ll almost certainly get lung cancer. Otherwise, people have swallowed it and injected it without harm. It can be shielded with a piece of paper. I have handled it in a glovebox with gloves that weren’t so different from household rubber ones.

But it’s plutonium that gives the “eternal” label to nuclear waste.

Enter President Jimmy Carter in 1977. He believed that reprocessing nuclear waste — as they do in France, Russia, Japan and other countries — would lead to nuclear proliferation. Just months in office, Carter banned reprocessing: the logical step to separating the cream from the milk in nuclear waste handling.

Since then, it’s been the policy of succeeding administrations that the whole, massive nuclear core should be buried. The chosen site for that burial was Yucca Mountain in Nevada. Some $15 billion to $18 billion has been spent readying the site with its tunnels, rail lines, monitors and passive ventilation.

In 2010 Sen. Harry Reid (D-Nev.) — then the majority leader in the Senate — said no to Yucca Mountain. It’s generally believed that Reid was bowing to casino interests in Las Vegas, which thought this was the wrong kind of gamble.

The industry had pinned all its hopes on Yucca Mountain being revived under Trump: He had promised it would be. Then on Feb. 6, and with an eye to the election (he failed to carry Nevada in 2016), Trump tweeted, “Nevada, I hear you and my administration will RESPECT you!”

In the Department of Energy, which was promoting Yucca Mountain, gears are crashing, rationales are being torn up and new ones thought up, even as the nuclear waste continues to pile up at operating reactors. No one has any idea what comes next.

Time, I think — after watching nuclear waste shenanigans since 1969 — to take a very fresh look at nuclear waste disposal. Most likely, a first step would be to restart reprocessing to reduce the volume.

I’ve been advocating that to leave the past behind, a prize, like the XPRIZE — maybe one awarded by the XPRIZE Foundation — should be established for new ideas on managing nuclear waste. The prize must be substantial: not less than $20 million. It could be financed by companies like Google or Microsoft, which have lots of money, and a declared interest in clean air and decarbonization.

The old concepts have been so tinkered with and politicized that nuclear waste is now a political horror story. Make what you will of Trump being on the same side of nuclear waste management as presidents Carter and Barack Obama.