Indonesia has an extremism problem. On May 9, a court convicted the sitting governor of Jakarta, Basuki Tjahaja Purnama, known as Ahok, to two years in prison for blasphemy despite a startling lack of evidence. The presiding judges issued this ruling under immense pressure from hardline Islamic groups, overruling the wishes of even the prosecution, which had recommended against a prison sentence.
The ruling sent shockwaves through Indonesian society, and outpourings of grief echoed across the nation. Indonesian politicians have been jailed in the past - often for corruption - but never has someone this prominent fallen victim to Indonesia's strict blasphemy statute. And never before has the impression of a "trial by mob" been so stark.
Only weeks earlier, Ahok had lost his bid for re-election after a campaign in which he was repeatedly targeted for his religion and ethnicity by hardline groups. As a Christian and an ethnic Chinese, Ahok is a double-minority among Indonesia's majority Muslim population. His ascent to the governorship of Indonesia's capital in 2014 was a milestone in the country's efforts to strengthen its respect for diversity and tolerance.
But despite this milestone, over the past several years, Indonesia has also seen an alarming rise in religious extremism and the growing popularity of hardline groups such as the Islamic Defenders Front (FPI) and Hizbut Tahrir Indonesia (HTI). These groups led mass protests calling for Ahok to be jailed - some of which turned violent - and pressured Muslim residents to vote against him because of his religion. Ahok's election loss and subsequent conviction are the latest and most striking signs that groups such as FPI may be gaining the upper hand - with the help of politicians who do not mind politicising religious concerns to win elections.
There has been plenty of hand-wringing about how Indonesia can confront this rising threat, and how countries around the world can address similar challenges. But we need not reinvent the wheel. For years, Indonesia has been viewed as a model of moderate Islam, and with good reason. There have been relatively few terrorist attacks in the past two decades, and the country does not suffer from the kind of significant radicalisation that many Middle Eastern or even some European countries have experienced.
Returning to 'Pancasila'
This reputation for tolerance is rooted in Indonesia's founding ideology of Pancasila, literally meaning "five principles", which is featured in the preamble to the Indonesian constitution dating back to independence in 1945. Pancasila's principles are: belief in God, shared humanity, national unity, democracy, and social justice.
In forging a path toward progress and away from extremism, Indonesia must return to its roots and redouble its efforts to strengthen the nation's resolve behind the unifying ideology of Pancasila.
This first pillar, belief in God, is distinct from embracing any one religion. Instead, it recognises the religious diversity that has existed in Indonesia for centuries and proclaims it as an asset. In this way, it forms the basis for Indonesia's historical embrace of pluralism and moderation. Under Pancasila, whether you are Muslim, Christian, Buddhist, or Hindu, you are a citizen of Indonesia and a valued member of society.
But the other pillars are equally important to sustaining a culture of tolerance. Commitments to shared humanity, social justice and national unity form the building blocks of an inclusive society, and democracy helps to ensure that the people's voice is heard. History has shown that respect for democratic freedoms, human rights and shared prosperity are some of the most successful tools for combating extremism in the long run.
Pancasila has served Indonesia well in the past as an ideology compatible with both Islam and human rights. It also presents a model for other nations characterised by significant ethnic and religious diversity. The Indonesian government has received official religious delegations from Muslim countries such as Iraq, Afghanistan, and Egypt, who are eager to learn from Indonesia's experience. Pancasila has also been used in crafting successful de-radicalisation programmes and strategies to counter violent extremism and terrorism.
But Pancasila itself is also under attack from hard-liners today. The leader of FPI, Rizieq Shihab, for instance, has argued that the pillar about belief in God should be more important than the others, even going so far as to criticise Indonesia's founding father, Sukarno, for his supposed downgrading of religion within the ideological framework he created. The argument is a clear attempt to undermine Pancasila by creating a battle over interpretation of its principles - a common tool used by extremists to dilute the power of alternatives to their preferred ideology.
The way forward
An effort, therefore, must be made to recover this influential indigenous ideology as a critical component of Indonesia's unique approach to confronting fundamentalism. Indonesian President Joko Widodo issued a decree on June 1, 2016 proclaiming the anniversary of the birth of Pancasila as a national holiday and urging the nation to reflect on the ideology's significance. This year, with Ahok consigned to a prison cell and the Indonesian public more polarised than ever, the second annual Pancasila Day should be an occasion to renew our commitment to tolerance.
As Indonesia's future appears increasingly uncertain, we must not give in to a narrative of "us versus them". We cannot abandon our democracy, our commitment to consensus-based decision-making, or our work to enshrine human rights principles in policy and legislation.
The nation already possesses the tools to confront this challenge - tools rooted in our founding documents and successful past approaches. In forging a path toward progress and away from extremism, Indonesia must return to its roots and redouble its efforts to strengthen the nation's resolve behind the unifying ideology of Pancasila.
Eva Kusuma Sundari is a member of the House of Representatives of Indonesia from the Indonesian Democratic Party of Struggle and Vice Chair of ASEAN Parliamentarians for Human Rights. She is also a founding member of the Pancasila Caucus in the Indonesian Parliament, which focuses on freedom of religion or belief. Before becoming a member of Parliament in 2004, she was active in the women’s movement and NGOs in Indonesia.
The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.