Footfall by Larry Niven

 

A huge interstellar ship is detected approaching Earth, but attempts to communicate don't get a response.  When the aliens arrive, they send small asteroids down to destroy strategic structures, such as power stations, major highways and dams.  The US and USSR launch nuclear missiles against the invaders' ship, but fail to stop the aliens.

 

Elephantine aliens land in central North America.  The US and USSR make a nuclear attack on the alien's position in Kansas, making it uninhabitable for both aliens and humans.  The aliens respond by dropping a relatively large asteroid into the Indian Ocean and landing a new occupation force in Africa.

 

This kind of war with the aliens doesn't look promising for humans.  A new secret plan is begun.  A spaceship will be build which uses nuclear explosions for fast and dirty propulsion.

 

Meanwhile, the aliens' relations with humans is working under assumptions from the aliens' culture / psychology.  To them, when one surrenders to another, that is the end of the conflict.  He who surrenders is possessed by the victor, and loyalty leads to increased status.  They do not anticipate an insincere surrender with plans of betrayal.  This sort of theme is not new here, but it is presented successfully.

 

There is also a storyline about differences among the aliens on their main spaceship.

 

The aliens in the book are atypical.  I'm not sure their anatomy is that likely, but it is not as impractical as some non-human aliens are.  While being generally elephantine, they have manipulative appendages at the end of their trunks.  And we see aspects of their society that have been molded by their physiology.

 

This is certainly a good choice for those who like "less-advanced-Earthlings fight back against more-advanced-alien-invaders" stories.  Although it's not one of the most extensive looks into alien beings and culture in SF, it may very well appeal to readers who like ideas about aliens.