For very small diameter circular knitting, you wouldn't be able to use a 12" circular needle because your tube of knitting would end up too large. But you also don't have to use double pointed needles! You can use the magic loop method with a longer circular needle cord or you can use the two circular needles method. I think both are demonstrated in videos on this site under Advanced Techniques.
Fear the Sock Monster! RAWR!
The individual has always had to struggle to keep from being overwhelmed by the tribe. If you try it, you will be lonely often, and sometimes frightened. But no price is too high to pay for the privilege of owning yourself.
Double Pointed - a knitting blog