William T. Cavanaugh argues against the notion that religion is uniquely or especially prone to violence:
The crucial point is this: people devote themselves to all sorts of things. People treat all sorts of things as their religion. With regard to the question of violence, people kill and die for all sorts of things; there is no good reason to suppose that people are more inclined to kill for a god than for a flag, for a nation, for freedom, for free markets, for the socialist revolution, for access to oil and so on. In certain contexts, ideologies of jihad or the sacrificial atonement of Christ can lend themselves to violence. In other contexts, belief in the free market or in Greater Russia or in the United States as worldwide liberator is what releases killing energies. If the biblical critique of idolatry is on the mark, there is no essential difference between the two, between religious and secular causes. There is no religious/secular distinction in the Bible. In the Middle Ages, the religious/secular distinction was a distinction between two types of clergy; it meant nothing like what we mean by it now. The way we now use the religious/secular binary is a modern, Western invention; it does not simply respond to the nature of things.
His broader point:
The idea that religion causes violence, in other words, can be used to blind us in the West to our own forms of fanaticism and violence. When we label our own devotions as secular, we tend to treat them as if they were not the subject of violence at all.
We are endlessly fascinated by the violence supposedly hardwired into Iran’s Shiite Islam; we prefer not to dwell on the Shah’s 26-year reign of U.S.-supported secularist terror. We remember that the ayatollahs imposed an Islamic dress code when the Shah was ousted in 1979; we forget that the first shah imposed a secular dress code in 1924.
It must be repeated—though it should go without saying—that nothing justifies the violence done in the name of Islam or any other faith. My point is simply that nothing justifies violence done in the name of secular faiths either, and that there is no essential difference between the two kinds of faith. Both are based on pre-rational narratives of belonging and deliverance. A sound approach to violence avoids making sweeping statements about religion, as if we knew what that was, and adopts a more empirical, case by case approach, on a level playing field between religious and secular ideologies and practices. Wahhabist Islam will not escape scrutiny in examining the Chechen conflict, but neither will secular, Russian nationalism. Forms of evangelical Christianity may be relevant to American military adventures abroad, but more so are secular, Enlightenment forms of salvation narrative that fly under the dangerously ambiguous banner of “freedom.”