你提的这个问题很难回答,因为美国很大,有很多的州。危险与否取决于你去哪里,我想说的是美国的确有危险的地方,也有安全的地方。总体来说,我觉得美国大部分的地方还是比较安全的。但是不管你到了美国任何一个地方都应该时刻注意你周围的环境,还有别去一些危险的地方(例如: ......If you can give some detailed examples as tips here, it will be easier for travelers to understand and helpful, because we really don't know what are the dangerous places you mean. Maybe it's something like common knowledge in the US. But as a new comer, we cannot figure out)。如果你能按照以上我提的建议做的话,来美国旅行应该没问题。