Editor’s Note: Ashley Frohwein, editorial assistant at The National Interest, posed the following questions to Kenneth Pollack, contributing editor at The National Interest and senior fellow in the Saban Center for Middle East Policy at the Brookings Institution, to discuss Pollack’s new book, Unthinkable: Iran, the Bomb, and American Strategy, as well as the situation in Syria.

Ashley Frohwein: To begin with, although we know now that sanctions did in fact compel Iraq to abandon its nuclear ambitions, the perception that sanctions weren’t working was a key reason for America’s going to war there in 2003. What lessons were learned—or should have been learned—from the Iraq experience that should inform efforts to contain a nuclear Iran?

Kenneth Pollack: This is a huge question, one that I discuss at length—and in a variety of different places—in my new book, Unthinkable. It's actually a very important point: our experience with Iraq has numerous lessons for our choices with Iran, in far more ways than most recognize. And the lessons run in a whole variety of different directions. They don't simply all reinforce one side or the other's preferences. Some of the lessons are favorable to the Right's preferences, and some to the Left's, and we need to acknowledge ALL of those lessons, not just the ones we happen to like based on our own political leanings.

I think that there are two lessons from the sanctions experience that stand out. First, the combination of intrusive inspections coupled with the pain of harsh sanctions succeeded—eventually—in convincing even Saddam Hussein to give up his treasured WMDs. Saddam did not want to give them up, and even after the beating he took during Operation Desert Storm, he tried for 4-6 years to hang on to at least part of them before he decided that he had to get the sanctions lifted and that the only way to do that was to give up his WMD program altogether—at least for a little while; he always planned to rebuild. That should give us confidence that if we can get the same elements in an agreement with Iran, it is unlikely that they will cheat. However, it also means that in any agreement with Iran we MUST have highly intrusive inspections AND we need to keep the threat of sanctions on the table at all times. It's why I favor indefinite sanctions suspension rather than complete lifting of sanctions.

The second key lesson is that sanctions take time to have their impact, but if they go on for too long, they can become self-defeating—and the timeframes can be identical. So it was only in 1995-97 that Saddam finally completely gave up his WMD programs, but it was in that same timeframe that international opinion soured on the sanctions and international support for them began to evaporate. As a result, we now know that Saddam had eliminated all of his WMDs by 2000, but the sanctions were hemorrhaging, with billions of dollars in illegal trade going into Iraq and dozens of nations ignoring the UN sanctions—including Russia, China, France, Egypt, and other would-be pillars of the international community. It means that if we don't get a deal with Iran, because of how harsh we have already made the sanctions against Tehran, we could see a similar erosion in support—and observance—of those sanctions in the next few years.

AF: In Unthinkable, you write that although the Iranian regime could last for several more decades, “it could also collapse within the next few years” and “things could get ugly” if Iran possesses nuclear weapons when this occurs. You also note that “a smooth, peaceful transition to a new government is quite possible, perhaps even probable” but that Iran could “dissolve into anarchy and chaos.” The latter scenario could compel the U.S. to go in to secure Iran’s nukes, a prospect that you suggest would be extremely difficult and fraught with uncertainty. Given this risk, should efforts to contain Iran if it were to go nuclear avoid actions that could increase the likelihood of regime collapse?

KP: If Iran acquires a nuclear arsenal, it would certainly be preferable to avoid the collapse of the current regime. Obviously, chaos and the possibility of civil war are not a good environment in which to have nuclear weapons floating around. The Pentagon purportedly has a contingency plan to try to move into Pakistan and secure its nuclear weapons in the event of regime collapse that supposedly calls for 75,000 troops. That sounds about right, and gives a sense of the degree of difficulty were we to try the same if that scenario became reality in Iran.

That said, this regime will not survive forever in Iran, although whether it ends with a whimper or a bang is impossible to know. It would be far better for Iran to experience a peaceful transition to a new government so as to avoid the potential for chaos under any circumstances; it just becomes that much more desirable if Iran has nuclear weapons.

As a final point, however, it is equally impossible to know what steps would make collapse more or less likely and what steps would make a peaceful transition more or less likely. In particular, as the Arab Spring should have made clear, doing nothing—or worse still, helping the Iranian regime to maintain the status quo—is no guarantee that state collapse would be avoided. Indeed, such periods have historically been the most likely cause of violent revolutions, and pressing for change in Iran may well be the best way to convince the regime to adopt gradual reforms instead. So while it is true that regime collapse would be even more dangerous with nuclear weapons, it does not follow that the US should not press for change in Iran; the historical evidence is unclear and it could be that pressing for change is the best way to avoid such a collapse.

AF: On October 3, Israeli Prime Minister Benjamin Netanyahu told BBC Persian TV that “If the Iranian regime gets nukes, the Iranian people will never be freed from tyranny and will live in slavery forever”, seemingly implying that a nuclear capability would shield the Iranian government from regime change, whether internally or externally instigated. Would possessing nuclear weapons bolster the regime’s ability to withstand domestic threats to its hold on power? Could going nuclear completely shield Iran from outside efforts to bring about regime change militarily?

KP: No. This is historical nonsense. Nuclear weapons did not prevent either the Soviet Union or the apartheid regime in South Africa from falling. And it is also worth noting that in neither case did the fall of the regime lead to the use of nuclear weapons, accidental or intentional. No other regime that possessed nuclear weapons has fallen, but there is simply no evidence to suggest that their possession of nuclear weapons allowed them to survive.

The United States, France, Britain, Israel, and India are all stable democracies. North Korea is a bizarre autocracy, but its nuclear weapons have not had any impact on the regime's ability to remain in power—at least in terms of maintaining internal control. There was never a threat from the North Korean people to overturn the regime that nuclear weapons might have affected. China's government has changed dramatically over the past 40 years, and nuclear weapons did not prevent that—nor was the one real challenge to the regime's control in 1989 affected one way or another by its possession of nuclear weapons. Finally, Pakistan's stability has deteriorated markedly in the past 10-15 years, and its possession of nuclear weapons has done nothing to stem the tide of its internal problems. As history has shown again and again, nuclear weapons are really only useful for one thing: deterring a conventional or nuclear attack on one's homeland. There is zero evidence to suggest that nuclear weapons have any bearing on domestic politics, let alone regime longevity.

AF: A number of commentators have argued that President Obama’s reluctance to follow through on his August 2012 “red line” against chemical weapons use in Syria by launching strikes against the Assad regime decreases American credibility, which could embolden Iran and make it less likely to make concessions over its nuclear program. Do you agree with this analysis, and if so, how significantly will this affect the prospects of reaching a negotiated, peaceful settlement of the Iranian nuclear issue?

KP: I am very wary of this analysis, and the argument that flows from it that the US needed to strike Syria to deter Iran from deploying nuclear weapons. First, I think one of the most important lessons of history is that you should not go to war with one country to impress another. From Korea to Vietnam, that kind of thinking has gotten us into lots of trouble.

Second, as a student of Iran and the U.S.-Iranian relationship, what is most striking to me from that history is how consistently we have misunderstood the Iranians and how consistently they have seen things in ways we never even imagined. At times, the Iranians have drawn the polar opposite conclusions from an event than what we assumed they would. On other occasions, they saw events through a completely different prism than we did, and so the lessons they learned had nothing to do with the lessons we thought they might. As a result, as I warn over and over in Unthinkable, we need to be very humble in assuming that we know how the Iranians will react in key circumstances. About the only thing that they have consistently demonstrated is that they have a very healthy respect for our power, and beyond that, anything is possible.