Thanks both to President Barack Obama’s willingness to evade the treaty-making process entirely in order to do his deals with Tehran and in Paris, and to President Donald Trump’s justified skepticism that it’s in the U.S.’s interests to stay in the INF Treaty while the Russians serially violate it, treaties are suddenly interesting again. But activists tend to ignore one of the more important questions regarding treaties: How will they be enforced? A second question follows logically: What will the U.S. support by way of enforcement?

One way to enforce a treaty is through a treaty-based international enforcement mechanism. A few years ago, along with a number of other think tankers, policy makers, and academics, I was interviewed by Professors Tora Skodvin and Jon Hovi of the University of Oslo for an academic article that sought to answer the question “Under what conditions should we expect the United States to support international enforcement of treaties?” That article can be found in volume 5, issue 2 of the 2017 number of Politics and Government, available here.

The question that Prof. Skodvin and Hovi pose is an important one, and the answer that they arrive at likely contains part of the truth. They conclude that:

We hypothesize that U.S. support is most likely for treaties where international enforcement will cause considerable (desired) behavioral change by other countries but little (undesired) behavioral change by the United States. Similarly, U.S. support is least likely for treaties where international enforcement will generate the converse effects. In developing this hypothesis, we derive specific conditions under which we should expect U.S. benefits of international enforcement to outweigh U.S. costs (or vice versa). We also provide empirical examples. Finally, we consider three alternative explanations of U.S. views on international enforcement—concern for U.S. sovereignty, desire to prevent infringements on U.S. constitutional protection of individual rights, and the usefulness of international enforcement as a domestic commitment device.

In other words, Profs. Skodvin and Hovi conclude it is a matter of costs and benefits: the U.S. likes international enforcement when it gets high benefits for low costs, but not when it gets low benefits for high costs. That is reasonable enough as a first cut, but that cut may not go deep enough.

One problem is that there are not all that many treaties have provisions for international enforcement. Profs. Skodvin and Hovi list five: the 1989 Montreal Protocol, the 1992 Chemical Weapons Convention (CWC), the 1995 WTO, the 1997 Kyoto Protocol, and the 1998 International Criminal Court. There is something obvious about these five agreements: they were all negotiated in the closing days of the Cold War or the palmy days of the 1990s. In others words, what Profs. Skodvin and Hovi are trying to explain with a general theory may simply be the artifact of a particular historical moment when the U.S. – having won the Cold War and reached ‘the end of history’ – was particularly willing to consider international enforcement, and when nations like Russia and China temporarily had less willingness to oppose them.

Second, the concept of “international enforcement” is trickier than it sounds. Profs. Skodvin and Hovi define it as referring to “the threat or actual use of material consequences.” By that standard, the Chemical Weapons Convention’s redress measures only barely qualify: the CWC’s Article XII allows its Conference of States Parties to “recommend collective measures” and to refer cases of particular gravity to the U.N. Security Council. Those are indeed threats, but no one who has watched the progress of Assad’s gas attacks in Syria will regard them as potent ones. In other words, it is not enough to know that a treaty has enforcement provisions: it appears to be possible for a treaty to have enforcement provisions that are too weak to count. It is likely easier to support weak enforcement provisions than strong ones.

By contrast, the WTO’s dispute settlement mechanism has more muscle. But whether this qualifies as “international” enforcement is less clear. The WTO is basically a form of mandatory arbitration of trade disputes. If the arbitration is not accepted, it results not in enforcement, but in retaliation by counter-measures. Of course, in many cases, the arbitration is accepted – but whether this counts as “international enforcement” is a judgment call, as it is not the WTO that imposes the material consequences or threatens their use: it is the nation that (successfully) complains of the breach of WTO commitments.

In other words, Profs. Skodvin and Hovi appear to have run together two concepts that are – or should be – kept quite separate: arbitration and enforcement. Judges, for example, are arbiters, while police are enforcers. In cases like the CWC, what the Conference is doing is actually closer to arbitration (judging whether or not an infringement has taken place): the actual enforcement is left to the CWC’s states parties, or in extremis to the U.N. Security Council (in other words, to the great powers).

So it may be that the U.S. will support what Profs. Skodvin and Hovi term “international enforcement” not when it has a lot to gain and little to lose, but when what they call “enforcement” is actually arbitration that, because the real enforcement is left up to states, is unlikely to be used in a concerted way against it. On the other hand, if an international organization could directly command actual enforcement, the U.S. would either have to follow its orders and (most likely) lead the enforcement (because few if any other nations have both the muscle to enforce and the willingness to use it), or resist its dictates. Few Americans since President Woodrow Wilson’s failure with the League of Nations have been eager to impale themselves on that dilemma.

Third, Profs. Skodvin and Hovi tend to assume that states are states – or at least, that there are just two kinds of states: great powers and regular states. As a legal matter, the assumption that states are states is fair enough. But this is a policy question, not a legal one. Thus – leaving aside the issues of sovereignty, which are to my mind sufficient reason on its own to oppose the ICC – the problem with the ICC may be that it embodies a particular kind of diplomacy (David Davenport usefully describes it as the ‘new diplomacy’) that relies heavily on NGO leadership and small Western nations (like Norway), which views great democratic powers with suspicion, inclines heavily towards anti-Americanism, and relies for its numbers on the accumulation of “small states that traditionally play little part in international affairs.”

In short, the U.S. may be less inclined to view states as simply and only equal, because that view – no matter what its legal merits – is not how diplomacy has traditionally seen the world, and in this regard as in many other diplomatic contexts, the U.S. is a traditionally-minded place. And that, in turn, undoubtedly makes the U.S. skeptical about a lot of “international enforcement,” because not all the units doing the enforcing are comparable. Either the U.S. will bear a disproportionate burden of doing the enforcing, or the enforcing will come mostly in the form of words or actions that are disproportionately likely to be aimed at it. That doesn’t disprove the cost/benefit hypothesis so much as it suggests why the U.S. calculation of costs and benefits is not likely to align with those of other democracies.

Fourth, and last, Profs. Skodvin and Hovi treat the U.S. as basically just another country – different because it is a great power and inclined to be scrupulous about implementing its treaty commitments and its sovereignty, but one that thinks about treaties in a standard way. That may not be true. In my view, the U.S. has, more than most if not all other countries, retained the view that treaties are just a fancy name for contracts between nations. This was the way the Founding Fathers – such as John Jay -- thought about treaties. As Jay put in Federalist #64, a treaty obtained by fraud “would, like all other fraudulent contracts, be null and void by the law of nations.”

One might think that this view of treaties as contracts would incline the U.S. to favor international enforcement. After all, if treaties are contracts, and we have judges and the police to enforce contracts at home, then surely we need something similar in the international realm. But actually, as Jay’s statement implies, the view of treaties as contracts inclines the U.S. to precisely the opposite point of view: that treaties are fundamentally enforced by mutual awareness of the mutual benefits that (should) flow from them, and that, if one side cheats or just opts out, the treaty is simply null and void. In the domestic realm, that is true of a contract – but not of a law.

In the domestic realm, contracts are almost always limited in scope and duration. Treaties, by contrast, are (in theory) usually forever. International enforcement – if it worked – would ensure that treaties actually did last forever, regardless of any changes in circumstances. So the U.S. view of treaties as contracts actually inclines it away from international enforcement, which would turn an agreement made for mutual advantage in the here and now into a perpetually binding pact. In short, it would turn a contract into a law. Now, a treaty is indeed a kind of international law – but not, as progressives like to imply, the kind that is binding on all parties, or on everyone, forever. Turning treaties into law would have obvious implications for U.S. sovereignty, but it is also simply not in keeping with the traditional understanding of treaties – which is based on pacta sunt servanda (agreements must be kept) in general, but also allows for clausula rebus sic stantibus (except in a fundamental change of circumstances).

In the specific context with which Profs. Skodvin and Hovi are concerned, this U.S. view – the traditional view – has two implications. First, it differs sharply from the progressive view that treaties are not contracts between nations, but rather unilateral commitments that a nation has made which must be upheld regardless of the non-performance of the other parties to the agreement. One can see this attitude clearly in the debate over the INF Treaty, where Trump’s critics, while often admitting that Russia has indeed cheated, find no justification for a U.S. withdrawal in this fact. This understanding of treaties as unilateral law-like commitments is also at the heart of most human rights treaties, which – as Profs. Skodvin and Hovi note – rely almost entirely on “reputation” effects for enforcement. At least some of the U.S. skepticism about such treaties thus stems from the fact that they cannot be understood as contracts. And as the “new diplomacy” tends to be based on the same doctrines that underlie these human rights treaties, this is another reason why the U.S. is skeptical about a vision of international relations that rests on empowering NGOs and very small nations.

Second, the U.S. view implies that international enforcement is a bad thing, and that it only makes sense when the treaty in question is about something that can be understood as narrowly commercial – in other words, when the treaty really is analogous to a business contract. Thus, of the five agreements that Profs. Skodvin and Hovi consider, the U.S. backed the stronger trade enforcement mechanisms in the Montreal Protocol and the WTO. It opposed the ICC and Kyoto, which are not commercial arrangements. The CWC is the odd one out – but then, its enforcement mechanism is so weak, and the U.S. has so little interest in chemical weapons, that explaining the U.S. support for the mechanism is not very interesting.

Of course, as a historian, I approach these questions in a fundamentally different way than Profs. Skodvin and Hovi, who as political scientists want a general theory. But that is part of the value of political science: it is not always (I would say often) capable of finding answers, but it is good at suggesting questions. To my mind, the question of whether, and why, the U.S. is on occasion willing to support international enforcement of treaties is fundamentally related to the fact that the entire U.S. treaty process – institutionally, legally, and mentally – has changed a lot less than the views of many other democracies. And so the best question may not be about the rare cases in which the U.S. supports international enforcement. It might instead be about what has changed in the way those other democracies view treaties which leads them to support something as untraditional as the international enforcement of treaties.