Reading the pieces within the 'Don't talk to strangers' link they do point out that societies can be altered in unexpected ways by the emotional and conceptual alterations brought on by contact. The Japanese society was centered around them being special. Arrival of an army and fleet far superior militarily to their own was quite a shock. It shattered their political, military, even their religious, systems and brought down a dynasty. The changes to the Japanese society set up the invasion of China and Japanese involvement in WW2.

Arrival of vastly superior aliens would drastically change the context of all human existence. US standing as superpower, and the secondary and tertiary standing of all other nations, puts things in a completely different light. Presently the US is, within the real and profound limits of any power, the final word.

What would the existence of aliens do to religious belief. Or the idea that humans are special.