The shoemakers of old took a pencil and a piece of paper, traced your foot, and made an enclosure for it. This enclosure has been enhanced with wheels, springs, air bags, flashing lights, rockers and what not, but mechanical function has not changed.
There are twenty muscles and twenty-eight bones in the human foot. The shoe of the future will be designed to react according with the entire set. There will be micro-machines embedded to relieve stress on the downstep, and recover energy on the upstep. The recovered energy could power the microprocessors inside the shoe running the show. In other words, the shoe will become as dynamic as the foot inside of it. Gone are the days when unyielding shoes will cause blisters.
There is only one problem that will arise with the modern shoe. Muslim extremist will find it easier to wire bombs into them, or make them better weapons for throwing at American presidents. Perhaps they will be made to go in planes in bare feet. It will go with their Stone Age views on religion.