i think divide and conquer was definitely in the mix, but lets talk about HOW they divided and conquered, the number #1 way is through offering one tribe arms or allegiance or manufactured goods, divide and conquer is based on the fact that the europeans had something valuable, and that something was technology and manufactured good and advanced weapons which made them valuable allies
and the same thing with ghadafi, who i am glad is gone, but any politics around ghadafii was based on the fact that western nations had technology that enabled them to drop bombs on him anytime and anywhere they wanted
the notion that technology is secondary or minor is nutty, technology is one of the main forces that drive and decide conflicts