And at the heart of the cause of alienation is a lack of respect for other people. It's a bad attitude. Removing alienation isn't simply a matter of tearing down walls and bringing people together to sing love songs. People who hate each other, fight when they get together - it makes things worse. Some people even need enemies to maintain their hold on togetherness or power.
Alienation serves a purpose of preserving identity, control, and power.
Recently even commercials blatantly appeal to the easily led, saying that buying an expensive car isn't about anything but power, as if flaunting power held more than temporary satisfaction. What we can't do is hide from those who feel alienated from us and will destroy us. Just building homes with walls around them, adding more locks on the door and security systems, sending children to private schools with more security, and driving an armored car isn't an answer. It's a poisoned vision of the future that believes we can't work it out, that too many people are too bad. In contrast, in some societies there is minimal crime and violence is rare.