Footfall is also the name of a book by Larry Niven and Jerry Pournelle. It covers "first contact", happening when an alien species reaches earth (approximately in the 90ties of the 20th century). Some fighting erupts which shows (and is maybe also partially caused by) the totally different ways of acting of humans and the aliens, which are quite detailed characterized. The end has a "humans are the best"-touch , though.

An interesting book showing how strange even familar looking aliens (they vaguely resemble elephants) can be.