The Japanese will likely lead in androids and humanoid robots. Personal assistants, nurses, sex partners, etc.
America will of course lead in weapons and spying. Drones are about to fill the skies and congress and the media will jump all over it and most of it will be fear mongering and distraction from real issues. Although there is huge room for abuse.
Look at this fearsome weaponization of big dog.
[video=youtube_share;ptyV1cpE14o]http://youtu.be/ptyV1cpE14o[/video]