If civilisation by conquest is such a dandy idea, then where is the Roman Empire today?
It’s gone. Just like the British and the Spanish Empires. But the fact remains that civilization - by that I mean transportation infrastructure, learning, technology, improved life expectancy, etc. - advanced wherever the Romans conquered. It’s a fact of history, friend. The region in northern and eastern Europe that was not conquered by the Romans stayed barbaric for a very long time. And some historians I have read hold that that is one reason Europe has never been able to unite.