With economic sanctions unfolding against Russia over its invasion of Ukraine, it’s useful to recall one of the climactic moments near the end of the Cold War — the dramatic weekend summit between President Ronald Reagan and Soviet Premier Mikhail Gorbachev.

This October 1986 meeting, held in Reykjavík, is remembered for nearly producing a deal to eliminate strategic nuclear weapons, but it collapsed at the last moment when Reagan refused to bargain away his missile defense initiative. But another aspect of the affair reveals a key defect in the Biden administration’s handling of the current crisis.

The drama of the moment led journalists at the time and historians after to overlook a significant small detail in the summit unrelated to arms. At one of their first one-on-one meetings, Reagan asked Gorbachev why the Soviet Union hadn’t paid for a recent purchase of American grain. Gorbachev was immediately testy: “You can tell [American farmers] that the money with which the Russians could have bought grain ended up in the United States and Saudi Arabia because of the sharp drop in oil prices.” Reagan calmly replied: “The oil business in the United States suffered greatly from the drop in oil prices. Many countries suffered because of the OPEC actions.” Gorbachev shot back: “We know that. We know who began this process of cutting oil prices and whose interests it is in.”

It was a remarkable admission by Gorbachev that Reagan’s deliberate campaign of economic warfare against the Soviet Union was working. The key role of oil prices is once again salient as the United States and its allies have declared a new campaign of economic warfare against Russia — and there are several parallels between that earlier policy and today.

Reagan decided to step up economic pressure against the Soviet Union in the aftermath of the Soviet-directed martial law imposed on Poland (a proxy invasion, so to speak) at the end of 1981. Now we have Russia invading Ukraine. Among the measures Reagan sought was an end to a Soviet natural-gas pipeline to Western Europe — shades of Nord Stream 2 today — though he only managed to delay its completion.

But by far the biggest factor in Reagan’s campaign to cripple the Soviet economy was engineering a drop in oil prices. Between 1981 and 1986, the price of oil fell from around $35 a barrel to $14. “Overnight,” one energy expert wrote, “the windfall oil and dollar profits the Soviets had been enjoying were wiped out.”

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How did Reagan help bring about this decline in oil prices (which also boosted the American economy)?

First, he encouraged domestic oil and gas production by removing the last price controls on oil and gas markets. Domestic oil production increased in the United States for the first time in more than a decade — and it wouldn’t happen again until the fracking revolution of the last decade.

But second, and more relevant to our moment, Reagan quietly and successfully persuaded Saudi Arabia and other friendly Persian Gulf producers to increase their oil output to lower the world price. To get this bargain, Reagan undoubtedly offered security guarantees as well as arms sales and other matters of interest to Gulf states.

The contrast with the Biden administration is clear. In addition to President Joe Biden’s open hostility to domestic oil and gas production, it is widely reported that the Saudis and other Gulf states won’t take his phone calls to discuss his request that Gulf OPEC producers increase output to make up for Russian oil removed from the market.

One reason for this standoffishness is obvious to everyone except the Biden White House: The Gulf states are appalled and deeply opposed to the administration’s craven drive to revive the Iran nuclear deal.

It is likely in the interest of Gulf OPEC producers for oil prices to come down from current levels. They’re enjoying a temporary windfall, but they probably maximize their revenues over the long haul with oil between $65 and $90 a barrel. And high prices incentivize competition, which they’d rather not have.

So their resistance to the president’s pleas ought to be a clear signal of how badly Biden is managing the related issues of Iran’s aggressive designs and the disruption of world energy markets. He could learn a lot from Reagan on effectively conducting economic warfare.

Steven F. Hayward is a resident scholar at the Institute of Governmental Studies at UC Berkeley and author of the forthcoming biography “M. Stanton Evans: Conservative Wit, Apostle of Freedom.”