“One at a time you can make them work and keep them safe,” Parimal H. Kopardekar, a NASA principal investigator, tells the Times. “But when you have a number of them in operation in the same airspace, there is no infrastructure to support it.”
This is something than can be both powerfully enabling as well as powerfully abused. Either through hacking or as a means to exclude people or organizations from participating. It will depend on how this is used.