After Indonesia’s democratic transition of 1998, dozens of small yet vocal Islamist groups sprung up throughout the world’s most populous Muslim majority country.
The Islamic Defenders’ Front (Front Pembela Islam or FPI) – the most notorious of these groups – has mobilised, often violently, to curb what it considers as immorality and misguided religious minorities.
The FPI, along with other Islamist groups, has played a key role in increasing polarisation and religious populism in Indonesia.
Aside from a few national campaigns, such as the “212” protest movement in opposition to Chinese Christian Basuki “Ahok” Tjahaja Purnama in Jakarta’s gubernatorial election in 2016, most of these militant groups’ activities are local, targeted at regional governments and minorities.
But these groups have had more success in some regions than others.
I have conducted a study of Islamist mobilisation in Indonesia’s main island of Java to understand why. I have recently published the findings of this study in Comparative Politics.
In that study, I found that militant groups have grown rapidly in regions where Muslim leaders and their institutions are weak and competition for religious authority particularly intense.
Militant mobilisation, I argue, is a byproduct of the local structure of religious authority – not of Islam as such, but of how it is locally produced and contested.
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Striking differences
In Java, some regions witnessed faster growth of Islamist groups and more persistent mobilisation.
Among all six provinces, West Java has the largest number of Islamist groups and the most frequent Islamist protests.
West Java saw nearly 60% of all protests and violence in Java since 1998. In contrast, East Java had only about 10% of the protests.
Several observers have linked the rise of militant groups such as the FPI to decentralisation and patronage politics in the post-transition period.
While part of the explanation, this does not explain why these groups tend to proliferate more in West Java since political incentives are arguably similar across Indonesia.
Others have suggested these militant groups cluster in West Java because of their link to the old Darul Islam networks. Darul Islam was a hard-line movement that sought to turn Indonesia into an Islamic state between 1942 and 1962.
I found little support on the ground for that theory.
Most chairmen of militant groups like the FPI, especially down at the kabupaten (regency) and kecamatan (district) levels, are otherwise mainstream kyai (religious teacher or elder) or ustadz (preacher). They operate small pesantren (Islamic boarding school), pengajian, or majelis taklim (Quran study group) and have no link to the Darul Islam.
Fragmentation in West Java
Provinces in Java vary in how Islamic leadership and institutions are structured, which is the key to understanding Islamist success in a province like West Java.
For this study, I conducted dozens of field interviews with Indonesian kyai and militant groups in 2014 and 2016 as part of my PhD dissertation research.
I also assembled a new dataset about the 15,000 pesantren and 30,000 kyai of Java.
The data I gathered allow for an unprecedented comparative perspective on Islamic institutions in Java. Here are some of the key differences.
West Java has more pesantren than East Java, but those pesantren are twice as small on average.
The map plots kabupaten with the smallest pesantren (in green) and those pesantren with more than 1,000 students (black dots) in Java.
As we can see, West Java has much smaller schools than any other region. West Java has only 26 schools with more than 1,000 students, while East Java has no less than 94.
Despite having more Islamic boarding schools, the map thus shows there are few influential pesantren in West Java.
There, pesantren are not only smaller but also collectively weaker. Inter-kyai networks in West Java tend to be thinner, more fragmented, and more informal than those in East Java.
This is reflected in the region’s organisational dynamics: although most people in West Java are traditionalist Muslims, Nahdlatul Ulama (NU) – the country’s largest Muslim organisation – is far from dominant.
Instead, the landscape of Islamic mass organisations is exceptionally fragmented. Most kyai tend to remain unaffiliated or members of smaller organisations.
In short, West Java has weaker religious elites and a much more competitive authority structure.
Why does all of this matter?
The influence of a kyai is inherently tied to the size of his pesantren and his network. Kyai with more students and more extensive networks with other kyai generally command more influence both inside and outside their region.
Influential kyai can better leverage their popularity to gain access, power, and resources in local governments, political parties, and Islamic institutions (e.g., the Ministry of Religious Affairs, Indonesian Ulema Council).
Low-status kyai, those with fewer students and weaker ties to other kyai, are much more peripheral and have fewer opportunities to exert influence.
Instead, they are precarious and have to be particularly entrepreneurial if they want to survive in the longer term.
The shortage of large schools in West Java thus means the province lacks influential kyai.
Although West Javanese people have a strong Islamic identity, Islamic authority is much weaker and much more competitive than in the rest of the island.
It is in this context that we can understand the rise of militant groups in West Java.
West Javanese kyai have much smaller pesantren and have to compete for students by using more aggressive religious rhetoric.
Joining or forming a new militant group, using morality and sectarianism, has become a powerful tool to expand religious authority.
Many small kyai have gained new followers and recognition from other kyai and policymakers precisely as a result of their mobilisation and assertive religious discourse.
In other words, their activities in militant groups have improved their status, influence and power, something they could not have achieved on their own.
The sheer number of small and precarious kyai explains the proliferation of militant groups in West Java.
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Stronger institutions in East Java
The situation is quite different in East Java.
Opinion surveys show that attitudes toward morality and religious minorities are in general quite similar across regions of Java.
East Java does not stand out as a more tolerant province.
A recent study shows that NU followers, many of whom are located in East Java, are just as intolerant of religious minorities as other Indonesian Muslims, and in some cases, they are even more intolerant.
However, the appetite for militant Islamist mobilisation is much smaller in East Java.
Here, it is not ideas but institutions that matter the most: kyai have big pesantren and strong inter-kyai networks and do not compete for followers and public attention as much as kyai in West Java.
This institutional structure and less intense religious competition tend to discourage entrepreneurship and strategies of religious outbidding.
The way to gain influence and power in the region is through Nahdlatul Ulama and achieving leadership positions in its numerous wing organisations.
To use militant mobilisation to achieve religious prominence in the region, as in West Java, would be counterproductive.
Moreover, because they have strong institutions below them, local kyai have found it easier – or less costly in terms of their reputation – to publicly oppose and contain militant groups’ activities.
Interestingly, many kyai in East Java have opposed militant groups for fear of being outflanked by new Islamic leaders, rather than because they oppose militant groups’ goals or ideology.
What should the state do?
In sum, variation in the local structure of religious authority, rather than political or ideational (cultural, theological) differences, explains militant groups’ success or failure in Java.
Where religious authority is strong, militant groups have been unable to take root. Where it is weak and competitive, militant groups have proliferated.
A key takeaway point is that governments should be wary of further weakening religious authority in the democratic era.
For example, governments should avoid creating too much space for religious inter-elite competition in Majelis Ulama Indonesia, as it increases incentives for militant mobilisation.