There is no reason why you should be afraid to travel. Many destinations have a very low crime rate, but tourists are an easy target. As long as you avoid trying to stand out, keep your passport in a safe place (and have photocopies in case it gets lost/stolen), watch how you carry your money, and take whatever other precautions you can to avoid becoming a crime victim, you will have a wonderful, worry-free time. Keeping a low public profile will also protect you against terrorism. Remain vigilant, keep strangers out of your personal space as much as possible, and stay alert. Thieves depend upon their victim being distracted, so as long as you avoid it, you will have no reason to fear.