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Center for War Studies

Generalized Trust and the Iranian Nuclear Deal

Written by Vincent Keating, Assistant Professor at Center for War Studies

On 14 July 2015, the P5+1 (China, Russia, United States, the United Kingdom, France and Germany), together with the European Union and Iran, put forward an international agreement called the Joint Comprehensive Plan of Action. This deal between Iran and the other powers aims to curb potential Iranian nuclear ambitions in exchange for a reduction in the international sanctions.  


On 14 July 2015, the P5+1 (China, Russia, United States, the United Kingdom, France and Germany), together with the European Union and Iran, put forward an international agreement called . This deal between Iran and the other powers aims to curb potential Iranian nuclear ambitions in exchange for a reduction in the international sanctions.  

The deal marks a potential shift in the otherwise unfriendly diplomatic relations between the United States and Iran.  For over a decade, tensions have been higher than normal because of US fears that the Iranians were developing a nuclear deterrent. This was worrying not only because it might create another nuclear state often hostile to US interests, but that it might also negatively affect the legitimacy of the Non-Proliferation Treaty.  

The deal is highly contentious within the United States.  Democrats have come out largely in favor, while Republicans have (with some exceptions) been against the deal. Given that the deal might help to alleviate US fears by keeping Iran non-nuclear and increase the breakout time of the Iranian regime, why is it so contentious?  I would like to argue that one way to understand the controversy is through the lens of what we call generalized trust.

The signatories announcing the Joint Comprehensive Plan of Action in Vienna. Photo by Bundesministerium für Europa, Integration und Äusseres (Iran Talks), via Wikimedia Commons.

The Importance of Generalized Trust in International Politics
Generalized trust is rooted in a psychological theory of trust. Brian Rathbun, probably the most prolific author on this subject, has argued that individuals, when making decisions to trust others, do not come to the same conclusions with the same information. Individuals, instead, will vary in their propensity to trust others. Some individuals, whom he calls generalized trusters, are more likely to trust others in any given situation. Other individuals, whom he calls generalized distrusters, are more likely to distrust others. This does not mean that generalized trusters only trust and distrusters mistrust – only that there is a propensity to trust or distrust given the same information. 

So who tends to trust and who tends to distrust? Rathbun says that the propensity to trust generally falls along the political spectrum. Liberals are more likely to be generalized trusters, whereas conservatives are more likely to be generalized distrusters. This has important ramifications for international politics. Where generalized trusters win domestic political victories on international issues, states are more likely to sign international agreements and get involved in multilateral institutions – without the need for escape clauses or other means to protect them against the potential defection of others.  

Rathbun has used his approach to explain why the United States signed up for the United Nations but failed to join the League of Nations. He also looked at the patterns of behavior in the creation of the North Atlantic Treaty Organization, coming to the same conclusion that the political success of generalized trusters is an important variable explaining why states join and how they shape multilateral treaties. Domestic politics thus has a large role to play in our understanding of international outcomes.  

Generalized Trust and the Nuclear Deal
But what applies to multilateral treaties that form security organizations might also apply to nuclear agreements. On the face of things, we can see these ideas playing out in US domestic politics. It is the liberal Democratic president and his administration who are the most supportive of the deal. Similarly, the conservative Republican representatives and leading presidential candidates are almost uniformly against the idea of signing the agreement.   

As expected, the conservatives would prefer a deal with tighter restrictions on Iran while the liberals are happier with a slightly looser (though still quite strict) agreement. Both sides have roughly the same information, but the fact that they come to different conclusions about the best policy reflects back on the propensity for liberals to trust and conservatives to distrust.

This is important because it highlights the importance of domestic politics on key moments within international politics. Though all states might be affected by the structural forces of anarchy, they will respond differently depending on the success or failure of particular political factions domestically. But it is also important for the Iranian nuclear deal in particular because it reinforces the saying that ‘all politics is local.’ Despite the amount of work put into the deal on the international level, domestic politics can still make or break potential diplomatic breakthroughs in relations between states. Generalized trust gives us a framework to understand this process.

Editing was completed: 23.09.2015