Do you think DoD did not think about it previously while they put transmitters on birds? I think it has to do with autonomy, speed (a real bird is more energy efficient, is more powerful and has a longer flight autonomy), and electronic signals betraying you (you have to physically come back with the data, not upload/transmit).
It's one thing to carry out experiments that might one day be used on a battlefield. Such pie in the sky thinking is pretty constant.
It's completely another to adapt a working prototype into a viable device, and as far as I know nothing to date has come as close as that video I just witnessed.
In addition, secure two-way data feeds in real time is pretty much a solved problem, and is currently being used on pretty much every UAV in existence today.
