Social cohesion was built into language long before Facebook and LinkedIn and Twitter - we're tribal by nature. Tribes today aren't the same as tribes thousand of years ago: It isn't just religious tribes or ethnic tribes now: It's sports fans it's communities it's geography.
The killer app that got the world ready for appliances was the light bulb. So the light bulb is what wired the world. And they weren't thinking about appliances when they wired the world. They were really thinking about - they weren't putting electricity into the home. They were putting lighting into the home.