I think they were trying to build an army of super soldiers and monster/human/robot hybrids to either:
1) For the country's national defence
2) To take over the world? (the evil theory)
3) To control the underworld and control demons, vampires, creatures of the dark
4) To make it a safer place for humans -- maybe they aimed to make the ubersoldiers protective of the human civilization, or so that they're under control & won't harm human beings (like with Spike's chip)
5) Simply just to experiment with science and see how far it can go
Perhaps a combination of some of the above?
1) For the country's national defence
2) To take over the world? (the evil theory)
3) To control the underworld and control demons, vampires, creatures of the dark
4) To make it a safer place for humans -- maybe they aimed to make the ubersoldiers protective of the human civilization, or so that they're under control & won't harm human beings (like with Spike's chip)
5) Simply just to experiment with science and see how far it can go
Perhaps a combination of some of the above?