James S. Robbins

Opinion Columnist

On Thursday two tankers in the Gulf of Oman were severely damaged by limpet mines. The United States immediately blamed Iran for the explosions. Secretary of State Mike Pompeo told reporters that the accusation was “based on intelligence, the weapons used, the level of expertise needed to execute the operation, recent similar Iranian attacks on shipping,” and the fact that no Iranian proxy group had the ability to conduct such sophisticated attacks. Secretary Pompeo also cited a long pattern of Tehran’s aggressive behavior in the region. And after all, it isn’t the United States but Iran that threatened to close the Strait of Hormuz.

Tehran quickly denounced Pompeo’s statement and suggested that the attacks were a false-flag operation conducted by countries in the region seeking to stoke conflict in the region. Iranian Foreign Minister Mohammad Javad Zarif tweeted, "Suspicious doesn't begin to describe what likely transpired this morning."

Neither the United States nor Iran have an interest in open conflict, though the escalation of tensions is reminiscent of the “tanker war” during the latter part of the Iran-Iraq War (1980-1988). Iran had begun attacking tankers from neutral countries that they suspected of carrying Iraqi oil, and any ships from nations supporting Iraq. The Reagan administration responded with Operation Earnest Will, reflagging Kuwaiti ships to bring them under the protection of the U.S. Navy and deter further Iranian aggression.

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Iran chose to test American commitment with a series of small-scale attacks involving laying mines and harassing U.S. and other ships with fast attack boats. The United States then conducted special operations against the mine layers and several larger scale attacks against Iran’s navy and Revolutionary Guard bases in the Persian Gulf. The tit-for-tat escalation stopped with the 1988 Iran-Iraq ceasefire, effectively ending the broader conflict. But President Ronald Reagan demonstrated American resolve in protecting neutral shipping and keeping the sea lanes open.

The main difference between the tanker war in the 1980s and the current round of attacks is that during the Iran-Iraq War both combatant countries openly attacked ships trading with their respective enemies. Iran’s covert mine-laying actions were monitored and easily detectable. There was really no question that Iran was the aggressor.

In this round of attacks Iran is not claiming responsibility, and evidence has not yet emerged publicly that would make the case against Tehran airtight. Iran complicated matters Thursday when IRGC naval forces made off with an unexploded mine on the side of the Japanese-owned chemical tanker Kokura Courageous, an operation the U.S. Navy caught on video.This makes it difficult if not impossible for independent investigators to assess where the weapon came from and who deployed it. To paraphrase Foreign Minister Zarif, suspicious doesn't begin to describe it.

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The case against Iran must move away from speculation and towards certainty. In his official statement Secretary Pompeo referred to intelligence evidence that Iran had conducted the mine attack. So, what is it? It would be useful if the U.S. government presented the facts to the international community in a way that would generate confidence for a unified response against Iranian aggression.

At the very least the White House could build the case for unilateral action of the type the United States took in the 1980s. This need not escalate to full scale conflict, but on the other hand Tehran does not seem content to accept Washington’s campaign of economic and diplomatic pressure without resorting to violence. And Thursday’s tanker attacks — as well as attacks on ships in May and other strikes at oil facilities — track with Iran’s threat a year ago that sanctions against Tehran’s oil sector would be “followed by an exorbitant cost.”

If the United States and other countries present solid evidence of Iran’s malign behavior it could deter future such attacks. Exposing Tehran’s culpability before the international community would also help justify counter-strikes should Iran continue this harassment campaign. President Reagan said over 30 years ago that he wanted to “make sure the Iranians have no illusions about the cost of irresponsible behavior.”

Maybe they need a reminder.