That is how old the Net is. Before the beginning . The earliest models of networking systems used circuit switching. Circuit switching was not flexible and the connections had to be maintained once made. But packets could, in case of a broken connection, route themselves through other available routes.
Packet switching is at the core of the Internet, as it exists today.
There are even a few neat diagrams. His prediction is that in near future it must become the chief, if not the only main medium, channel of communication between people on and off the web. The US department of defense gets interested. That is, in other words, with packet switching, you are not limited by the existence or otherwise of a specific network route for communication. That is part of the Internet folklore.