That means it is still impossibletosend a packet of calls as photons from New York to Chicago, route some locally and send the rest on to Los Angeles--without first converting the signal into electrons.
For the 15, 000 or so Chinese men who had come to build Canada's transcontinental railway and the many more that came thereafter, it became first prohibitively expensive and then impossibletosend for their wives and children.
If people think that their private photos and videos can be shared in a manner that is truly self-destructing (as has been ingrained thanks to movies such as the Mission Impossible series) they are more likely tosend them to others.
The TSA has defended the scanners, promoting their built-in privacy protection measures including blurring of faces and making it impossible for the machines to store or send the images.
Suddenly people could do something that had previously been impossible: you could broadcast your public key to the world, allowing anyone tosend you messages that only you could read.