Earth VS the Flying Saucers (1956) directed by Fred F. Sears

 

One of the lesser know Ray Harryhaussen films, mostly because of the lack of giant monsters I think. Its interesting to see stop motion used for spaceships, robot aliens and scenes of destruction, though. It's very typical of film of this type... aliens arrive and humans attack them so they assume (rightly) humans are hostile. Things escalate and there is an all out war between the saucers and the military. 

It's really hard to think of the aliens are the bad guys, though the story keeps trying to show them as cold killers, they only kill when attacked, at least at first. The film is hardly a Star trek episode, the earth people never really try to makes things work and the saucer people who have kidnapped the main female character's dad and a police to suck information out of their brains (promising to put it all back later) throw the bodies out of the ship from the air in a horrifying scene after the military shows it can makes their spaceships lose control. As shocking as this is it's still not more horrible than the humans having already murdered several of the visitors right from the start. The whole thing ends in a spectacular fight over Washington DC which destroys several well known buildings and monuments until the "invaders" are destroyed and things go back to normal. 

The looks of the spaceships and aliens are cool, the flying saucers are exactly what you think they would look like and the robot suits that contain the aliens are unique... sort of goofy and stiff but original in design. The stop motion destruction is well done and pacing is quick enough between effects shots to keep you interested.