A recent article in Foreign Affairs suggested that the Peace of Westphalia – the 1648 agreement ending the Thirty Years War, fought primarily between Europe’s Protestant powers on one side and Catholic powers on the other – could serve as a model for ending the Shia-Sunni rivalry currently fueling instability in the Middle East. If this model is to bear fruit, it will require careful diplomacy to ensure commitments from the main regional powers (Iran, Saudi Arabia, Turkey) as well as support from outside powers (the EU, the US, and Russia). It will also require acknowledgment that the means that largely brought an end to sectarian strife in Christendom will have to be substantially modified in order to be effective in an Islamic context.

The Peace of Westphalia suggests itself as a model today not simply because it resolved a sectarian conflict, but also because it established norms for future relations between the powers involved in that conflict. Those norms have been expanded and revised over the centuries, but their core has stood for so long in the West that they have essentially become unspoken assumptions, fading into the background of our everyday expectations about how the international system works.

Religious differences presented an impediment to official communication between states in the pre-Westphalian world. An ambassador sent from Catholic Spain to the Protestant Dutch Republic, for example, would find no place in his host country to hear mass or take communion. The Dutch ambassador, on the other hand, could not legally bring a Protestant book of prayer or a vernacular Bible with him to Spain. The Peace of Westphalia solved this problem by vesting embassies with extraterritorial rights: the Dutch embassy in Madrid was on Spanish soil, but Dutch law took precedence within the embassy itself. The embassy chapel could thus hold Protestant services without breaking Spanish law; the Dutch would reciprocate by providing the same privileges to the Spanish embassy in the Hague. The particular legal status of diplomatic missions remains enshrined in international law today.

This legal device invented to facilitate diplomacy illustrates the most revolutionary feature of the Westphalian blueprint: it recognized religion as separate from, and ultimately subordinate to, political order. Ideally, pre-Westphalian rulers were expected to enforce religious uniformity not just among their own population, but universally. After all, how could a just ruler withhold the Word of God from his own people? What earthly jurisdiction was not under the sovereignty of the King of Kings? Such was the standard line of thought among European powers before 1648. But after 1648, any Christian ruler who wished to confer with his peers had to acknowledge boundaries on religious zeal.

The Peace of Westphalia was one of many gradual steps leading to the secularization of modern Western society, in which the right of conscience makes each individual a virtual embassy unto themselves. The modern liberal state aims to provide citizens with security and prosperity, assuming their spiritual life to be a private affair. It would be wrong, though, to see the Westphalian blueprint as having arisen from some sort of innate human tendency toward liberty; rather, it arose in a specific context to address a specific problem: finding it unsustainable to engage in the subjugation or slaughter of so-called “heretics” decade after decade, European rulers simply took religion off the diplomatic table.

As the authors of the above-mentioned article recognize, Westphalia is an imperfect fit for the current Shia-Sunni conflict. The Protestant and Catholic nobles of the Holy Roman Empire, where most of the fighting of the Thirty Years War took place, all agreed to accept the jurisdiction of the Holy Roman emperor and his courts of law as the venue in which to resolve their disputes. In what I consider the weakest part of the article, Axworthy and Milton suggest the United Nations as the superior jurisdiction to which the Shia and Sunni states of the Middle East would defer. I believe that a better possible venue for the management of sectarian conflict exists in the form of the Organization of Islamic Cooperation (OIC).

To return to the issue of European precedents: the office of Holy Roman emperor had an explicitly Christian origin, having been bestowed on the Frankish king Charles the Great by Pope Leo III in the year 800. By the sixteenth century, it had detached itself from the papacy, instead drawing its legitimacy from a College of Electors drawn from the clergy and nobility of the Empire. Historically, the closest equivalent to the office of Holy Roman emperor in the Islamic world was the Caliphate, but that office was abolished when the Ottoman Empire dissolved in the aftermath of World War I (the claim of Abu Bakr al-Baghdadi to have revived it notwithstanding).

Given the absence of a personal office that can wield jurisdiction over rival powers, the OIC represents the best alternative. Every Muslim-majority country, whether Shia or Sunni, is an OIC member, and the organization has already drafted action plans for protecting religious minorities in the member states. Moreover, the OIC has established an Independent Permanent Human Rights Commission that, if so empowered by the member states, could theoretically acquire the judicial means to resolve disputes that Axworthy and Milton suggest handing to UN courts. It would require recognition (and likely some form of monitoring) by the EU, the US, and Russia as external guarantors, but it could ultimately serve as an ecumenical forum for resolving sectarian disputes in the Islamic world.

Thus internationally recognized and legally empowered, the OIC could serve as a sort of “Concert of the Middle East,” formally assuming the kind of role that the nineteenth-century Concert of Europe played in maintaining stability on the continent following the defeat of Napoleon Bonaparte. Would that then somehow deliver modern Western secularism to the Islamic world? The answer to that has to be an emphatic “no.” The history of secularization in the West is fraught with contingencies and contradictions to the degree that, as scholars like Charles Taylor and Michael Allen Gillespie have pointed out, it might make more sense to regard secularism as an offshoot of Christianity rather than as an independent belief system opposing Christianity. The near-term goal here is simply to end the current conflict; the longer-term goal is to sustain the peace. To do that in a meaningful and enduring way, existing regional institutions will need to foster a sense of Islamic ecumenism presently in short supply.