The deal struck by Iran, Brazil and Turkey is obviously inadequate to the goal of preventing Iran from acquiring a nuclear weapon, but one of the important subtexts of the deal is the emergence of new powers capable of tackling a pressing international issue. Indeed, some commentators have urged the administration to take the Turkey/Brazil deal precisely because it ratifies this emerging, multipolar diplomacy.
Regardless of how you feel about the merits of the Turkey/Brazil deal, I think their gambit affords the U.S. an opportunity to have a fundamental debate about which international issues and interests are truly vital (i.e. uncompromisable) and which are not.
In his recent speech at West Point, President Obama said that: "As influence extends to more countries and capitals, we also have to build new partnerships, and shape stronger international standards and institutions....This engagement is not an end in itself. The international order we seek is one that can resolve the challenges of our times... "
I think the opposite is likely to happen. As influence extends to more countries with different security and economic interests, it will be increasingly harder to find common ground and the efficacy of international institutions will likely lesson. President Obama thinks that reforming international institutions is the answer, but why do we think that giving other powers greater say will improve effectiveness, when what constitutes effectiveness is going to vary by country? One need only look at Copenhagen, or the details of the Turkey/Brazil fuel swap deal to understand that.
In such an environment, the U.S. is going to have to do a better job not simply playing well with others (which will be important) but also at defining which interests are truly vital - and not amenable to the kinds of lowest common denominator trade-offs inherent in international diplomacy. I doubt that will be easy. For years now, Washington has been downright promiscuous with the phrase "vital interest."