A different Cold War

Like British Borneo (including Brunei), it joined Indonesia at independence, or soon afterwards. The post-colonial states of Southeast Asia (and future members of the EAU with Japan and united Korea) are Thailand-Cambodia, Vietnam-Laos, the Malay Union (including Singapore, but not northern Borneo), the Indonesian Federation (including northern Borneo and East Timor, but not West Papua), and the Philippines. In the neighborhood there are also Tibet, Burma, and Papua-New Guinea (including West Papua), but I'm uncertain about their alignment by the 21st century, except Tibet in all likelihood stays a client of India, or might well even join the Indian Union if/when it democratizes enough. The Indian Union absorbs everything east of Iran and Afghanistan, south of Tibet, and east of Burma at independence. The USA annexes Australia, New Zealand, and pretty much all of Oceania either by the 21st century as the final evolution of the NAPU or after WWII.

Yes, the two halves of New Guinea got peacefully unified during decolonization - the Western powers enacted a little rearrangement that gave Indonesia a united Borneo and Timor but lost it West Papua. Much like OTL, united New Guinea stayed an Australian colony a little longer then eventually got self-rule. It probably became an associated state of Australia/NAPU/USA or alternatively the EAU. I'm uncertain if by the 2010s it has acquired a sufficient degree of socio-economic and political development to be a full member state in its own right of either union. For the reasons given upthread, full independence is certainly possible but definitely unlikely.

Tibet in all likelihood became somewhat more democratic over time thanks to the influence of India and the Western powers, probably enough to qualify as a constitutional monarchy, even if not necessarily a British-style one with a dominant parliament and a figurehead monarch. I would expect the Dalai Lama to keep a lot of prestige and quite possibly important executive or at least reserve powers as a revered national symbol, even if by the 21st century Tibet probably stopped being a theocratic absolute monarchy. Because of the persistent Chinese threat, the Tibetans may be expected to seek a strong bond with their Indian protectors over time. Yet as far as I can tell, statehood in the Indian Union requires a republican form of government, like for the USA (this is a trait that differentiates America and India from the EU and the EAU among the Big Four). So the end result may well be Tibet becoming an associated state of India for the foreseeable future, unlike the Indian princely states, Bhutan, and Nepal that were simply annexed by India during decolonization.   

It essentially happened as a result of negotiations between the Dutch, British, Americans, and pro-Western Southeast Asian leaders during decolonization. A notable feature of TTL decolonization process is the Western powers do not necessarily rubber-stamp colonial borders or administrative divisions as the borders of post-colonial independent states. They often make an earnest effort to create states that may be more resistant to destabilization, in possess of a better amount of resources, and/or more stable in demographic, economic, strategic, political, and ethno-religious terms. The Watsonian, in-universe cause for this is a mix of factors including decolonization happening in a slightly slower, more ordered, and less anti-Western way, Communism being seen as more of a threat, the Americans being more involved in the process, the indirect effects of European integration and the Chinese disaster, certain colonial powers such as France having less freeway with their colonies due to their defeated enemy status, etc. The Doylist, out-of-universe reason is this is supposed to be a rather optimistic TL, especially for the Western world at large (and so it callously uses a screwed-up Russia, China, and Middle East as eggs to make the omelette of a better world for the Americas, Europe, and the rest of Asia), and this includes a nod to a less dysfunctional decolonization process.

By the way, this is a reason the TL and its author are mostly silent about most of post-colonial Sub-Saharan Africa. It doesn't look like much of a necessary or especially useful ingredient for the omelette, but I do not have many good ideas on how to adjust the decolonization process of Africa to make the continent substantially less dysfunctional and kinda skeptical the situation could be radically ameliorated with a WWII divergence, apart from a few exceptions such as making a stronger, less racist South Africa unite and develop most of Southern Africa.

Certainly not anything of the size of West Papua, and all residual small European colonies, if they still exist at all, became the purview of the EU as a whole decades ago. Admittedly the EU has more than enough resources to maintain a dozen or so small islands and exclaves across the world with no significant effort for the foreseeable future. On the other hand, to keep these possessions would be very, very low in its priority scale and as far as I can tell, they would provide Europe no significant benefit in terms of increasing its already huge prestige, wealth, and military power. Thanks to their GSO integrated military alliance with the USA and the EAU, Europe can easily access any possible basing resource they may need for global force projection capability by cooperation with their allies (and this is of course true for America and East Asia as well). The only significant benefit I can think of for keeping these small colonies might be as a spaceport if the location is near the Equator, but with the current state of advancement of spacecraft propulsion technology ITTL, I do not know if the point would be technically relevant anymore. Chemical rockets have largely gotten obsolete, and the world powers have not yet gotten to the point of having the technological capability to build space elevators.

If anything, the significant issues in terms of territorial/colonial expansion that absorb the energies and attention of the EU by the 21st century include complete assimilation of its most recent member states and least developed areas (Serbia, Bulgaria, Greece, Ukraine, Romanian Moldova), possible further enlargement in the former Soviet space, and space colonization. Due to the possible effects of Soviet-era demographic changes and the possible security concerns caused by Islamism, I'm not entirely sure if the EU is seriously contemplating further enlargement in former Soviet space, but it is entirely possible and perhaps even likely that at least Belarus, Georgia, and Greater Armenia are in the future enlargement agenda. If they stay as secular as OTL or better, Greater Israel, Kurdistan, and Greater Azerbaijan might well be in the EU enlargement agenda as well, although in these cases, security concerns about acquisition of a (larger) land border with instable, hostile, terrorist-ridden Middle Eastern countries might give Europe serious pause. Otherwise, the only colonies that are any really relevant for 21st century Europe and the other world powers are the space ones. The four world powers are very busy planning and preparing for a transition to mass, large-scale colonization on the Inner Solar System, to send millions and dozens of millions to near-Earth space, the inner planets, and the asteroid belt, start extensive exploitation of the resources of these areas, and down the line engagé in terraforming of Mars and Venus. The next Age of Colonization is upon mankind, pretty much everybody on Earth that isn't trapped in more pressing survival concerns realizes it, and the world powers are very determined to take the lead and reap the benefits.

In this regard, the issue of whether a few small islands and tracts of land in the Americas or the Pacific still belong to the EU or were ceded to the USA or the EAU seems beyond trivial, especially since the trade would happen between close allies and long-standing partners that share a similar federal and liberal-democratic political system and high levels of development, in a globalized, cosmopolitan developed world that is increasingly coming to see nationalism and non-civic patriotism as entirely wrong, outdated, and harmful. Of course, it would be entirely different if an European, American, or East Asian possession would be threatened with takeover by an anti-Western rogue power. But the global balance of power being as it is, the swift, massive retaliation of the attacked superpower or the GSO at large would surely cause the utter destruction in short order of the regime that attempted such a suicidal folly. Nobody but the Islamists would be mad enough seek a confrontation with the GSO powers, and they can't do much worse than their terrorist attacks. 

Honestly I find this tiny-islands issue quite annoying and irrelevant. Depending on political butterflies, it might go both ways, but if I have to choose an option, I much prefer the one that provides the greatest geopolitical neatness and continuity, which in most cases seems to rule counter to the continued existence of these small remnants of the old European colonial empires or their transformation in tiny, useless independent states. With TTL superpowers increasingly going out of their way to squeeze parasitical tax havens and offshore financial centers out of existence, it seems the main potential source of livelihood and practical reason to exist for the latter option is getting extinguished anyway.

The former, pretty much since its birth. Creation of a Pan-European army was one of the founding features of the European integration process back in the late '40s - early '50s, one of the reasons it got so much more successful than OTL and Europe grew into a superpower of equal prestige and economic, political, and military power to the North American-Pacific USA and superior to everyone else. The original EDC system included a pan-European military divided into national components at the battalion level with centralized military procurement and a common budget, arms, and institutions. We can expect with complete federalization, growth of a strong Pan-European identity, education promoting widespread multilingualism in the last few European generations, and likely transition of the US and EU militaries from conscription to an all-volunteer system after the end of the Cold War (although the former remains potentially ready to be reactivated in an emergency), European military centralization has progressed even much further, and hence the US and EU armies have grown largely indistinguishable in structure in most regards. This also because the two sister superpowers (and later their younger EAU sibling) have been influencing each other to a common standard in many fields during and after the Cold War through the GSO integrated military alliance. GSO integration and standardization is as advanced as OTL NATO or even better in many cases, since it is much easier to establish a common standard and efficient division of responsibilities between three big members of near-equal strength than a couple dozen of widely different capabilities. One important difference between OTL NATO and TTL GSO is with growth of the alliance to a global reach thanks to integration of Australasia and East Asia during and after the Cold War, as well as the persistent security threats from, and instability in, Russia, China, the Muslim world, and Africa even after the fall of Communism, it was fairly easy for GSO to explictly redefine its role and mission as a global peacekeeping organization and self-appointed world policeman.

One of the very few remaining areas where the member states of the EU and the EAU may still perform as separate actors is sports competitions. A standard has evolved where the world powers sometimes compete as a unitary whole, sometimes with their member states or various sections/regions as separate entities. For team sports, there are events where Europe, America, East Asia, and India compete with their own teams, and others where separate member states or regions (France, Germany, Italy, Japan, Korea, Vietnam, the Midwest, Australasia, the West Coast, etc.) field their own teams. For individual sports, often both the state/region and the nation/union of an athlete get tallied to establish the score of both areas. In many cases, a third level exists, where teams of different cities compete. All three kinds of competitions draw considerable interest, although the by far most popular and economically-valuable events tend to be world (or at least federal/continental) ones where the global (or federal/continental) best of the best get established, be them federal unions/continents, nations/regions, or cities. As a rule, teams of different levels do not compete with each other, and they established balancing standards to try and ensure participating member states or regions in the sub-federal competitions are not too different in size, population, and wealth, and/or their teams not too unequal in strength. However these rules (like pretty much everything in international law) are written by the world powers and geared to protect their interests, which in the sports field means to ensure a fair and interesting competition between them, rather than with the rest of the world. Nevertheless, in recent years South America has been fairly successful in adapting to this system and fielding both continental and national/regional teams of its own to compete with the world powers as a near-equal, especially in certain sports, even if its own political integration process started later and remains so far incomplete, or at least delayed. Likewise, thanks to their vast size and population Russia and China are often allowed to compete in the highest continental circuit and may face the Big Four as potential rivals, even if they are underdogs perennially plagued by widespread suspicions of, and sometimes caught red-handed at, using illegal means to try and close the gap.

The sports competitions system is broadly similar to OTL, if with a few more events. One difference is a greater level of Western-dominated globalization led to a fairly high level of homogeneization and standardization in the relative popularity of various sports across the world. They tend to be uniformly very popular, not so much, or not really so, in all areas of the (developed) world (e.g. association football, basketball, baseball, various combat sports have grown very popular pretty much everywhere), and it has become fairly rare for a sport to be remarkably popular in one area of the world but of minor importance in others (such as say gridiron football, which declined to minor status in North America ITTL).

Another important difference is for pretty much all team sports, a double-track system has evolved: one circuit where the big states and continental/regional unions compete as unitary entities (there are European, American, East Asian, Indian, South American, Chinese, Russian, etc. teams) and another where their components (states or regions, as the case may be, with the intent to keep things roughly balanced) compete as separate actors (there are French, German, Italian, Japanese, Korean, Thai, etc. teams). For the latter kind of events, even those federal unions and big states that did not arose from the fusion of nation-states with distinct identities or only partially so (North American-Pacific USA, Greater India, China) have established separate teams for their own sections/regions (or states if they are big enough) (so there are a New England team, a Bengal team, and so on) out of imitation and a wish to compete on equal terms. The golden rule is teams of different levels from states that take part in both circuits never participate in the same event (if there is the EU team, the French one cannot participate, and vice versa).

So say soccer World Cups are actually split between a "States'/Continents' Cup" and a "Nations'/Regions' Cup" (actual names may vary) and the same division exists for team sports competitions within the Olympics. States that aren't big and diverse enough to participate in the double-track system are theoretically free to take part in either kind of event (the national circuit is relatively easier, the continental circuit is more prestigious). Both kinds of events tend to be of similar high importance for the most popular sports, but the continental circuit has gradually grown more popular and prestigious for various reasons, most importantly the widespread perception that it hosts the most elite and 'best of the best' athletes, teams, and matches. Again taking soccer as an example, there is also a different kind of federal/continental competitions that may include national/regional teams or city clubs rom the same continental area, and aren't much different from the OTL national and club continental championships. These may often be very popular and prestigious too, but not so much as world events.

For individual sports, fans, media, and governing bodies simply adopted the system of tracking the state/union and the nation/region of the athlete at the same time to establish the score of both, so say an European Italian swimmer wins a bronze medal for the EU and for Italy. Although the political integration of South America has been rather slower and looser than the ones of Europe, non-UK Anglosphere, and non-Han East Asia (but there are growing signs they may close the gap in the near future), the double-track system has been popular and successful enough to motivate the South American nations to create a joint continental team of their own, which has grown into a worthy competitor of the world powers in several sports. Africa and the Muslim world have been simply too instable, weak, disorganized, and conflict-ridden to set up anything equivalent of similar effectiveness, although they have been a few partially-successful efforts, which created awkward situations about the representation of these areas in competitions, because of the exclusionary rule. Russia and China are usually understood to qualify for the double-track system on their own because of their size and population (although the Russians are a fairly controversial borderline case), so controversies about them in the sports world mostly arise because of their infamous record about doping, corruption, and similar issues. Surviving independent small and middle states often claim the double-track system unfairly favours the big ones, but their complaints invariably fall on deaf ears. 

A few scholars and observers have remarked the emergent multi-tiered organization in the sports world, which seems to pattern and align with fan preferences fairly accuretely, appears to mirror a similar growing pattern of multi-tiered, compatible, and complementary group identities (global, continental, regional, local) based on cosmopolitan, civic, secular, liberal, and humanistic factors and ideals that increasingly displace, downplay, and marginalize old ethno-religious and cultural identities and affiliations for many citizens in the developed world, especially in the last few generations. This shift seems widespread among members of Gen-X, Millennials, and Gen-Z, fairly frequent but far from universal in the latter portion of the Baby Boomers, relatively rare in the older generations, most prevalent in the upper and middle classes and across most of the Western/developed world (especially the USA, Europe, Japan-Korea, and part of Latin America). They argue this phenomenon has been both a cause and an effect of cultural-political globalization and post-WWII socio-political changes, and may portend to further radical changes in the future. They also claim the conflict between this emergent pattern in the Western world and resistance to it in the Muslim world has been among the causes for the rise of Islamism, of course in combination with several other historical factors.