This is a concept that has been in my head for quite a while, It's soft-ish Sci-Fi, but I really do like how this sounds.
So, in the year 2110, humanity finally ended their massive third world war, entire continents are scarred with nuclear fire, radioactive craters dot the landscape, and the scars of battle were present all throughout the world. Most notably in the 'losing' side of the war (I.E China and Russia, I'll get back to that later). Europe, Both North and South America, Parts of East Asia, Parts of SE Asia, South Asia, and a small chunk of the Mideast and Africa were the only major areas where post industrial society were still active and running. The apocalypse, the dreaded china (with allies) vs the usa (with allies) scenario has come and gone. And another chapter of humanity is beginning the unfold.
With entire chunks of the planet now a radioactive wasteland, and a massive immigration crisis of Chinese, Central Asians, Russians and some eastern europeans flocking into the wartorn victorious countries, a relative period of instability reigned, from the year 2120s to the 2160s. Intermittent terrorist attacks by people from the 'losing side' of the war continued, in the meantime, sovereign governments, now having to handle not only the refugee crisis, but also the pressures of decontaminating wasteland, continuing with reversing the effects of climate change, and just general expenses of doing governing duties, started to unify one after the other, it all started with the pan-atlantic-pacific trade deal, a massive trade deal involving the North American Union, European Federation, Japan, Unified Korea, and China (Taiwan became the Defacto ruler of China after the collapse of the PRC, ruling Taiwan and whatever parts of China not irradiated). But the effects of that trade deal is the slow but steady unification of humanity, eventually culminating in UN resolution A/RES/250/1055. Or better known as the Unification act, that finally ordered humanity under a single representative democratic government.
This period is known as the 'intermittent' period. Where the world is kinda Cyberpunk but not really. The government is weak, there are some serious problems plaguing governments worldwide, and technology is advancing nonetheless. VR, AR, Virtual Waifus, Megacorporations (heavily regulated), and Rampant Crime are all happening, but under the guise of a democratic government, even though the democratic governments, although ultimately the only viable mode of government left, is plagued with massive issues after the end of the third world war.
The construction of the first FTL drive, made in the year 2210, finally allowed humanity to map and colonize the stars. And it wasn't long that humanity discovered that they weren't alone in this universe. Contact with the first alien life happened in the year 2220, and soon enough, humanity realized that their positioning in the universe is not necessarily the best. During the intermittent period, other alien empires had a roughly 100 year jumpstart. Colonizing star systems left and right, humanity is now left with a small chunk of the orion arm, a handful of star systems with colonizable planets, and a essentially living in a 'crowded out' part of the universe. So, with external expansion effectively impossible, humanity turned to their few star systems they had, and started making a home for themselves in what is effectively undesirable property in the galaxy. Earth is too far away from the major centers of power like the Empire of the Eternal Sovereign and the Tiar-Maki Republic, only resting in a region of space where, although Earth is technically stronger than their nearby neighbors, nobody on earth desires an interstellar war as their first way to greet the galaxy. Not to mention that the military advantage Earth had is relatively minuscule to their neighbors.
Skip forward some 80 years later, and the Federal Republic of Humanity has completely transformed itself from a desperate nation with their home planet wartorn and irradiated, effectively the laughing stock of the entire galactic community, with some alien races thinking humans got past the big filter by accident, into a relatively small, but very, VERY advanced country in the galactic stage, humanity, with Earth and a smattering of a few colonies, became a massive business hub for people from all over the galaxy, the Human economy, powered by a combination of 'highly urbanized colonies', planets whose colonization involved hundreds of millions of people being shipped off immediately, with a massive support fleet constructing everything from cities to farms immediately, a very lax immigration law that allows practically anyone in, corporations that manufacture everything from spaceships to smartphones, and a very effective 'university to market' pipeline. Essentially bringing in the forefront of innovation from human universities into the wider galactic market rapidly (results may vary), Humanity has essentially became SPACE!Singapore, with the small caveat that their government is extremely democratic. A small, but powerful trading nation with a military that is not to be laughed at.