John Daniel Davidson explains in a Federalist column why Muslims who don’t believe in violent attacks on the Western world have some work to do.

… [M]any of us in the West need to understand distinctions that moderate Muslims seem to take for granted. I recently argued that if ISIS and its underlying ideology are to be defeated, the Islamic doctrines that animate it must be discredited—not just by a crushing defeat on the battlefield but also by moderate Muslim leaders around the world arguing for a peaceful version of their faith. We in the West have no competency to judge which interpretations of Islam are valid and which are not—no matter what President Obama and Secretary of State John Kerry say. If moderates have a compelling case to make, they’d better start making it.

They don’t seem to be up for the challenge. After the attacks in Paris and San Bernardino, Muslim groups like the American Council on American–Islamic Relations (CAIR) and the Islamic Circle of North America (ICNA) were quick to condemn the attacks and distance themselves from “radicalism.” But none of these groups have ever addressed head-on one of the central claims of ISIS and other Islamist groups, which is that Muslim societies (including non-Muslim minorities) should be governed by Islamic law, or Sharia.

Setting aside who should decide the correct form of Sharia, is this something most Muslims believe? Is it a radical belief or mainstream? According to a 2013 Pew survey of Muslims, huge majorities of Muslims in the Middle East, Africa, and Asia say they agree that Sharia should be the law of the land.

Muslims in the West shouldn’t be offended if their fellow Americans or Europeans are uneasy about admitting large numbers of people who hold such a view into their countries. Combined with Islam’s political origins and its history of conquest, many westerners conclude, not unreasonably, that Islam is fundamentally illiberal and an Islamic “reformation” is impossible.

But instead of lecturing westerners about Islamophobia, moderate Muslims would do better to address candidly how something like Sharia can be reconciled with Western values. Tell us, in other words, why Islamist groups like ISIS are wrong for wanting to impose a Muslim theocracy, and tell us what Sharia and jihad mean if they don’t mean what Islamists say they do. We are capable and willing to understand.

Alas, westerners have at least some reason to suspect that moderate Muslims have no good answers to these questions.