Depends on our current direction. Obviously, the future is unpredictable, so instead, I’ll present two scenarios; one being the worst of all possible timelines, the other a more realistic one with tinges of optimism.
The Worst: Civil wars, regional conflicts, genocide, and terrorism divided and weakened the world in the first half of the 21st century, greatly dividing the world and leaving economies in shambles, along with hundreds of millions dead. Meanwhile, a nonchalant response to global warming open the floodgates (get it?) to a ravaged world, and economies plummeted as wealthy regions went asunder, and millions of climate refugees were left bereft in their own countries. Diseases and natural disasters greatly increased, and the wars that characterized earlier years continued.
The wealthy elites continued to push for their vision of global oligarchy, hijacking space travel and using all off world colonization as ways to exploit interplanetary resources. The concept of a job died by 2100 due to automation, as the poor got poorer and the rich got much, much better. Governments died and were replaced with loosely associated corporate conglomerates, treating their “citizens” as customers.
By 2217, hope is dead. Billions are dead due to corporate negligence, natural disasters, disease, and war. The super-wealthy have long since abandoned Earth, living in lavish off world colonies. Anyone on Earth lives in a sort of Anarchic limbo, fighting each other over the few resources remaining as robots attempt to quell the chaos. All of humanity will be extinct by 2500, and anyone left will be mostly automated.
A Better Tomorrow: The world stood united against climate change, and while they couldn’t stop it entirely, many steps were taken to reduce its impact, as many renewable energy sources replace those of old, almost completely negating the risk of a resource war. Automation was handled properly, as governments around the world provided a Universal Basic Income, which in turned increased the corporate drive for lower prices, further driving up quality of life for all. Genetic modification and human augmentation provide nigh-immortality for anyone who wants it, which in turn greatly diminishes the religions of the world, though cults rise up with ideologies for the new world.
The concept of a government will certainly see much change, though this change is so radical it’s completely unpredictable at this point. Off-world colonization provides plenty of new homes for people, with completely different “nations” arising on these planets. Many new resources enrich the Earth, and economies boom. Hell, by 2217 we may have even made first contact. At that point, Earth will mostly be made up of a few massive unions/superstates, and the off-world colonies will from their own unions.
Of course, this is all speculation. So many events could change the course of the future, and the real tomorrow will probably fall someone in between these scenarios.Ultimately, the future is fluid, like all things, and while it’s subject to change, we as a species can be that change, temper the unpredictable events of tomorrow, and use it to create ourselves that ideal world.