Every religion thinks it's the only one that has it "right."

And throughout history, there has always been one religion willing to kill to prove its point.  Even worshiping the same god is not protection against religious terrorism.  Sectarian violence in the Middle East today isn't any different from the Catholic/Protestant violence of 20th Century Ireland.  

Conclusion:  Faith isn't the problem, it's doctrine that is unhealthy for human life.