The argument that is sometimes made is that the only real signifier of how advanced a civilization is, is their ability to destroy or subjugate everyone else. This view holds that any other kind of societal advancement is not real because it can be nullified by someone with more military power. It doesn't matter how great your architecture is, how efficient your irrigation, how egalitarian your socio-political system, or how pretty your art is because all of that can be wiped out by a more powerful invader. Unless you can defend your advancements, they may as well not have existed at all. And it is usually implied that the only way to defend your own civilization is by destroying or subjugating all the others around you, because if you don't do it to them they will eventually do it to you. The same people that hold this view usually also believe that all real societal progress is a byproduct of advancements in military prowess.

Unfortunately i don't think you can really reason with people who think like this, they just have a radically different set of fundamental values that is incompatible with our views on society.