"Now armed with this knowledge there are many disorders that we could fix if we had a way to deliver the right DNA. In many ways gene therapy is like the Cold War. We have nuclear warheads but it isn't going to do any good if we don't have an effective delivery system. A delivery system must first be able to hit the target but it must also allow the device to do its job and do it covertly enough that it doesn't call up the defenses of its enemy too quickly."