The only argument for it, is that a government based on right of conquest bothers even less to take account of the people's wishes than current European governments, if that is even possible. What are they going to do, after all? Allow 14,000 girls to be raped? Arrest you for jokes about the government?

But still: the cost vs. benefit is rather unfavorable. Even if a conquest would be marginally worse, it would not be worth risking one's life over.