The present day was sometime in the very early 22nd century. There has been a collision between a post-Soviet Russian-dominated aggregation and the United States, a minor nuclear war that shattered both polities and led to a general reorganization of the world. A Europe that stretches to the eastern frontier of some of the Russian states is a federal state of note, as is a South America organized on comparable lines, and greater China as well, and likely India, too. Other more traditional polities like California, Mexico, Japan, and South Africa are minor powers.
There is now no global hegemon, or any global hegemony. After the 2030s war, law and order globally have been maintained by a status quo coalition of federations, ceding some power to overarching planetary authorities, more to interlocking networks of national and federation governing structures. The world is safe, but it isn't a global democracy, not be any means.
Wealth and technology have advanced greatly since the reconstruction of the 2030s, and the geographical divergences in income have mostly closed. They have been substantially replaced, however, by global class differences, with a cosmopolitan elite of politicians, businesspeople, and others benefiting hugely from their status as powerful individuals. The global elite just managed to be in the right place at the right time to cement its privileges.
Space is settled, after a fashion. There are automated research and mining stations scattered throughout the Solar System, and thanks to a jump drive of sorts, even in other nearby planetary systems. Space colonization just isn't economic. Near-Earth space is heavily developed, as a sort of preserve of the global elite (habitats, communications and manufacturing stations, others), but space settlement is basically a Ponzi scheme (invest in asteroid mining to bring metals to L5 to build a L5 colony to build solar-power satellites via nanotechnology ...) Mars is an exception, reachable via normal space and a self-selected preserve of the elite's colonists. A binary planet in the Tau Ceti system, reachable only through a jump drive that commands the power behind very minor astronomical events (and thus reachable only via UN jumpships), is another, the main planet as hospitable as Earth, the other a wet Mars.
Things are unstable. Too much power is afoot, and things are too decentralized, for there not to be an explosion. The only saving grace is that not enough people have enough power to do serious damage, so far.
The 2030s geopolitical trauma that I mentioned is decidedly old, even Cold War vintage. Where, for instance, is Iran and Pakistan, or the whole of the greater Middle East? What happened to China, Europe, South America, India? Great power conflicts don't necessarily have to implicate everyone, but the collapse of the world hegemon and at least one regional superpower has system-wide ramifications. The fragmentation of larger nation-states does seem possible--we may indeed end up talking about the Russias, the Canadas, the Americas and Chinas even, by this time next century.
The choice of Tau Ceti as the home of my young binary planet seems dubious, since that star seems to not only be ten billion years old but to be surrounded by an extraordinarily dense cloud of asteroidal and cometary objects.it's better to move this pairing to the nearby and much younger planetary system of Epsilon Eridani.
I don't think that the technology or the society need to be changed very much. If anything, the shift towards transhumanism and social polarization seems to be deeper than I ever imagined at the time.