So I'm working on a novel right now which is set in a global hyperpower known as the United Earth Republic. In the aftermath of a devastating, total-nuclear World War 3, the UER rose from the ashes of the old world in 2033. Using technology that was reverse engineered from ancient underground artifact vaults, they pushed back the three deadlocked superpowers of the war and finally ended the conflict by conquering the planet.
However, in the wake of all the destruction the war brought, the UER wasn't going to let history repeat itself again. For the first time, humanity saw an era where war was abolished. Instead of using our technology and skills against each other, the United Earth Republic unified Humanity under three guiding destinies: To push technology forwards, to solve our biggest issues together, and (most importantly) to explore, colonize, and conquer the final frontier of space.
As a result of the UER's direction for humanity, alongside a number of newly-found artifacts to do so, we managed to paraterraform Mars by the 2040s, we discovered FTL travel by 2045, and we settled 4 different exoplanets across 3 different systems by the 2060s. All under complete world peace.
My question to you is how I can make such an peaceful, expansive empire such as the UER exist. Without removing the ancient technology or the war (they are huge plot points), what would the UER have to do to be this successful as a hyperpower?