I think that there are some violent people who profess the Muslim faith, but that does not mean that Islam is itself a violent religion any more than Christianity is a violent religion simply because violence has been perpetrated in its name.
Tempting as it may be, it is naïve to attempt to capture any great religious tradition in a few simple categories; such an approach inevitably leads not to simple statements but to simplistic ones.
There are, and have been for centuries, traditions within Islam that are as embracing of peace as any of us could hope. What is, however, relatively new to Islam is the encounter with a highly pluralistic world.
Generally speaking, Islam, like many religions, does not have a long tradition of existing without the benefit of being the established religion of an area. The notion of a pluralistic society in which religions are expected to co-exist peacefully is a comparatively new and challenging concept.
Rather than accusing Islam of being a religion of violence, we should work with those many partners within Islam that embrace peace in the search for a better and more peaceful world in which all people live safely in just and equitable societies.