There are a lot of misconceptions in the western world when it comes to Buddhism. Since most of us were raised in a "Christian household" as my mother called it, we see any religion as requiring us to believe in something because most of them actually do require us to believe in something in order to be a practicing member of said religion. This is not the case with Buddhism. Buddhism might assert certain beliefs such as reincarnation for instance, but such beliefs are not at all required for one to be a practicing Buddhist. All that is required to practice Buddhism is to practice Buddhism. Practicing Buddhism basically consists of being a moral person (or someone who practices universally preferable behavior), and meditating, which I personally have found to be an extremely beneficial practice. This also means that there are really no dividing lines in Buddhism that would conflict with any other set of beliefs (although, most other religions tend to advocate behavior that would conflict with morality). Therefore someone could conceivably be a Christian and a Buddhist at the same time, though being Christian might cause one to act immorally.
Since Buddhism requires no beliefs to practice it, Buddhism does not conflict in any way with atheism, because atheism is a fundamental lack of belief in forms that cannot be proven logically (God, Jesus, Ala, etc). Buddhism is essentially an instruction manual for life, one which advocates morality, peace, tolerance, and understanding.
There are no rules in Buddhism, only optional guidelines. No Buddhist would advocate punishment for any immoral act because the concept of Karma says that immoral acts contain their own inherent consequences and so punishment is futile. Karma, when looked at objectively tends to hold true for the most part. If you commit acts of violence against people they will retaliate, or the victims DRO will retaliate in their place. But even if someone were to get away will an immoral act, the best course of action is not to retaliate, but simply to repair the damage done and to act preventively to avoid further acts of violence against ones self (purchasing an alarm system, avoiding bad neighborhoods, not socializing with unstable or violent people etc), which is also a concept that is taught by Buddhism. So Karma is not so much an empirical truth, but a psychological tool to avoid people using violence to end violence (as a government would).
Since Buddhism advocates non-violence, tolerance, and understanding, I believe the more wide-spread it becomes the less violent the world around us will become, and the closer we will be to achieving a stateless society.
Here is a podcast that I have been listening to for about a year that has helped me understand the finer points of Buddhism as well as achieve a deeper understanding of certain aspects of life in general: Ajahn Brahm friday night talks.
If you find you disagree with any aspect of Buddhism or its practice, I welcome your responses.
Act without doing; Work without effort; Confront the difficult while it is still easy; Accomplish the great task through a series of small acts.