Long-time observers of Indonesia's politics and economy are a hardy, stubbornly optimistic crowd. That's because we've seen through too many dire predictions of collapse, disintegration and chaos to believe the scares.

Our vulnerability is the other side of the coin: Complacency.

Indonesia is vast in every sense. But simply realizing that doesn't mean we haven't overlooked one of the most important implications: There are worlds in Indonesia that are completely removed from the eyes of most analysts -- particularly Western ones. Many of these worlds are harmless. Some, however -- if allowed to come to full bloom -- bode very ill for Indonesia's future.

In My Friend The Fanatic: Travels with an Indonesian Islamist, Sadanand Dhume takes the reader into one of these dangerous worlds. His encounter is facilitated by Herry Nurdi, then managing editor of the fundamentalist Indonesian magazine Sabili. Sabili, Dhume reminds, declared Abu Bakar Bashir, the head of terrorist group Jamaah Islamiyah, its "man of the year" a few months after the 2002 Bali bombing.

Herry, in his conversations with Dhume, takes credit for bestowing on Bashir this honor, which was offered with the proclamation, "If Bashir, most of whose life has been devoted to upholding Islamic sharia law, should be called a terrorist, being terrorists might as well be our goal." In another interview, Bashir himself connects the dots of the global Islamist network by invoking the most famous terrorist of all. "Osama bin Laden," Dhume quotes Bashir, "is a soldier of Allah. His bombings are not action, but reaction."

It is easy to dwell on terrorism. The price it exacts in human misery is so dear. Indeed, the reference to bin Laden in Dhume's book is chilling. But in the case of Indonesia, which has not had a major terrorist attack in three years, terrorism is not the only radical threat it faces. As a prominent Indonesian Muslim political figure recently told me when I asked about the threat from terrorists and political extremists, "What's the difference? All of them want to establish an Islamic state."

Sabili's affinity for Bashir goals, regardless of his tactics, and Bashir's apology for bin-Laden's terrorism should be seen in this light. They know what many Indonesians know: In and of themselves, tactics don't matter. What matters is achieving their totalitarian political vision. And it is, indeed, a grim vision for all but their leaders.

Party chieftains, office holders and supportive intellectuals will win the same trappings of power enjoyed by their pancasila-abiding counterparts. Individual Muslims -- abangan, santri, modernist, conservative, liberal -- who hold different views of their faith will be the ones to suffer. Christians and other minority groups will be shunted to the vulnerable edges of society. And peculiar Islamist priorities will undercut the competitiveness that is the currency of prosperity.

Dhume gives us a glimpse into the future on a tour of a "sharia-minded" government school in South Sulawesi. Conveniently across from the school in Bulukumba stands an old mosque. On the school grounds, despite its extreme educational needs (one broken computer for 450 students) another mosque is under construction. Dhume sees in this ordering of priorities a broader lesson. He is not gentle in his commentary: "While Indians learned computers and maths, Chinese crammed English, and Vietnamese ratched up worker productivity in factories, here they were building a little mosque right next to the big mosque. Who would dare oppose it? Who would say, 'Excuse me, but might there be a better way to spend this money?'"

Although Indonesia's famous easy-going everything-will-work-out attitude may rub off on visitors, the secret is it is not entirely what it seems. In fact, many Indonesians are worried about the future of their country. And much of their anxiety has settled on Prosperous Justice Party (PKS), its electoral prowess and its ability to obfuscate its real agenda. Dhume's insight into the PKS is the most important part of the book.

For anyone uncertain about the PKS agenda, Dhume's interview with PKS Secretary General Annis Matta is revealing. When asked about sharia, Matta responds, "Indonesia is not ready. All laws should be applied only after society is ready to accept them. I can't say 'cut off a thief's hand' if people are poor and there is no food. We have to remove obstacles in society before implementing it. If you have laws without conditioning the people first, it will fail." A similar thought is expressed to Dhume by Irfan S. Awwas, executive chairman of the extremist Indonesian Mujahidin Council (MMI): "In Indonesia there are too many prostitutes to stone and thieves with hands to be chopped off. We can't implement it immediately." He goes on to identify democracy itself as sharia's biggest obstacle.

"My Friend the Fanatic" is very honest. Rarely does a journalist reveal as much about his personal perspective. You learn a few things about Dhume from reading the book: One, he has an appreciation for the Jakarta night scene, and two, he is an atheist. The honesty is admirable. But it opens him up to criticism. And it's only his personal perspective and its implications with which I have any major disagreement.

The choice in Indonesia is not as stark as between the excesses of Jakarta's nightlife and the nightmare of Islamist government. One can be fully a democrat and at the same time opposed to libertinism. The question becomes where one draws the line and how to do it in a way that preserves universal fundamental freedoms.

An atheist point of view is not going to carry the day in Indonesia -- any more than it will in America. Only faith will successfully compete with Islamism for the Indonesian hearts and minds. For this reason I disagree with Dhume's dismissal of Indonesia's Muslim moderation. The well-springs of Indonesia's rich spiritual traditions and tolerance are deep. And only these -- and institutions to support them -- can hold back tyranny. Unfaith is not up to the task

Walter Lohman is senior research fellow for Southeast Asia in the Asian Studies Center at the Heritage Foundation.