I think the real point that is being made here is that it is easier for a civilization to uprise and attack their government or domestic military than it is to completely restructure a society or governmental system to incorporate the ideals of the culture. This is especially the case when there are not clear leaders in the rebellion. For instance, there is currently a rebellion happening in Syria, however, there are so many different rebelling groups that there are no clear leaders since there is not one homogenous rebellion, as was the case in the United States revolutionary war. Hope this helps.