No imagination is necessary: we've been there. The 1800s were exactly that and culminated in two world wars on the next century.
Speaking of the 1800s, I wonder if we could learn anything about peace in a multipolar world by studying the Concert of Europe. Might be a good topic for a historian to write a book about. I'm looking right now, and it's kinda sad to see so many books about WW1 and so few about the peaceful period which came before.
Just the 1800s? We’ve been doing for the past 150 years at least
You can even go further, _all_ human history had stronger groups taking things from weaker groups. On the classical era of Aristotle and on the paleolithic pre-history. We sometimes forget that humanity can be cruel and work only for self-interest, we like to think that war and pillaging is something from the past, but it will be forever with us