Last May, President Trump withdrew from the nuclear agreement that President Obama struck with Iran. Now, many fear that the Trump Administration may be on the verge of a military strike on the country. Tensions with Iran began escalating rapidly in April, when Trump announced that he was designating the Islamic Revolutionary Guard Corps a terrorist organization and imposed more sanctions. Last Thursday, two tankers, one Japanese, the other Norwegian, exploded in the Gulf of Oman. The Trump Administration quickly blamed Iran for the attacks, and for attacks on four other tankers in the same area on May 12th. Then, on Monday, Iran announced that it was likely to breach the nuclear deal by keeping more uranium stockpiled than is allowed by the agreement, as the U.S. prepared to send a thousand more troops to the region.

To talk about the state of U.S.-Iranian relations, I spoke by phone with Wendy R. Sherman, the lead American negotiator on the nuclear agreement, and a former State Department ambassador. She is currently the director of the Center for Public Leadership at Harvard Kennedy School, and the author of “Not for the Faint of Heart: Lessons in Courage, Power, and Persistence.” During our conversation, which has been edited for length and clarity, we discussed the risks of escalating tensions, why Trump has taken such distinct approaches to Iran and North Korea, and the difference between hard-liners and hard-hard-liners in both the U.S. and Iran.

Do you have a view other than agnosticism on who was behind these tanker attacks?

I have not seen the intelligence myself, so it is very hard to definitely say what occurred here. Nonetheless, the fact that the chair of the House Intelligence Committee [Adam Schiff] has publicly said that he believes the intelligence is conclusive is certainly an important data point. I think the real issue here is not only what happened but why did it happen, what will be the response to it happening, and is this part of an escalatory cycle that was begun by the Trump Administration when the President withdrew from the J.C.P.O.A. [the Joint Comprehensive Plan of Action, as the Iran deal is officially known]?

What is your sense of American policy toward Iran right now? Do you see any rhyme or reason, or anything that could even be called strategic belligerence?

I do not think there is a coherent policy or strategy regarding Iran. I think President Trump made a commitment during the campaign to withdraw from the deal. His then [team] all believed he should not. When they all departed, his new team supported his withdrawing from the deal. Within that new team, I would say we have the never-saw-a-war-he-didn’t-want-to wage national-security adviser, John Bolton. We have a chief of staff, Mick Mulvaney, who pretty much endorses everything the President says. We have an acting Secretary of Defense [Patrick Shanahan, who withdrew from the confirmation process on Tuesday] who clearly doesn’t have a voice in this Administration, it appears. And we have a Secretary of State [Mike Pompeo] who may think he is trying to bring nuance to this policy, but seems to be pursuing a path which, either intentionally or by accident, may take us to war.

Maybe I am picking up on something that is not there, but I thought you sort of described Pompeo as thinking of himself as a voice of moderation or compromise. Is that based on something you have heard?

I think “moderation” is too strong a word. I think Secretary Pompeo may believe that he is talking with all of the allies and partners, and trying to make sure everyone is aware of the intelligence. But there is no question that he has become what I call a hard-hard-liner, and not a hard-liner. We are all at some level hard-liners when it comes to Iran. Nobody wants Iran to have a nuclear weapon. And nobody wants Iran to continue malign or nefarious behavior in the region or in the world, or human-rights abuses, or its state sponsorship of terrorism. But the hard-hard-liners are on the ascent in the Trump Administration, and hard-hard-liners are certainly on the ascent in Iran. And that has created a virtual symbiosis where the hard-hard-liners in each of these spheres have ramped up an escalatory and very dangerous cycle.

One concern among opponents of the Trump Administration was that by ramping up sanctions and being more aggressive, the United States would only embolden Iranian hard-liners. What have you seen that suggests that has already occurred?

Think of it this way: it is actually rather extraordinary that, even in the face of the Trump Administration withdrawing from the deal, and the reimposition of sanctions, and the ramping up of pressure, Iran has stayed compliant with the deal. But the Supreme Leader of Iran has always understood that for his survival, he needs to balance the forces in his country. And there are hard-line forces—I would probably call President [Hassan] Rouhani a hard-liner—and there are hard-hard-liners—the I.R.G.C. and the Quds Force. And clearly the hard-hard-liners are in the ascendancy, because they have said, “Enough already. Being part of this deal has gotten us more sanctions, more pressure. We have gotten nothing out of this. We told you all along that the deal was a bad deal.” The I.R.G.C. never wanted this deal. They owned the black market. They owned the Iranian economy. They would like to go back to those good old days. They want freedom of action in the Middle East. Apparently, they have it. On the day the Prime Minister of Japan was in Tehran, if the intelligence is accurate—and, as I said, I haven’t read it, so I don’t know—they attacked a Japanese tanker.

You are saying that even people like yourself in the Obama Administration who wanted a nuclear deal and people like Rouhani, who, in the American press, is generally called a moderate, are hard-liners. Everyone is a hard-liner. Is that accurate?

I don’t think that President Rouhani is moderate in American terms. He is a very conservative cleric. He believes in the theocracy of Iran; he is a product of it. And he is a hard-liner. People would call me a moderate in U.S. terms, because I was willing to negotiate with Iran under the direction of President Obama and Secretary [John] Kerry, but I am in my own way a hard-liner, because I believe Iran should not have a nuclear weapon. It should stop locking up Americans in Evin Prison. It should stop its state sponsorship of terrorism. And it should stop its human-rights abuses of its own people.

Right, I just meant that it’s interesting that we are at a place where there are really no doves—

I am more of a dove when it comes to finding the strategy and the tactics that can address these issues peacefully, as opposed to war. That is not to say I am a pacifist. I am not. There are times when war is the last and only result. But what we are experiencing right now is an escalatory cycle between the hard-hard-liners in each of our countries. They are spinning each other up on a path that could lead us to a war that is unnecessary, in my view, and will be horribly destructive.