Of course, the war is not yet over, but it is reasonable at this time to extrapolate the current state of the war to its reasonable conclusion: a crushing defeat for IRON, more pain for Polaris and most of Purple, and a painful and damaging draw between TOP and C&G. (C&G will probably be able to claim a victory in the end, but both sides are going to lose in that encounter.) So what can we say about the likely shape of the political landscape afterwards?
The first and most obvious outcome will be a grave weakening of Polar's influence. They have already lost their connection to the Superfriends (Ragnarok having cancelled that MDP on Monday), and it seems likely that the Mushroom Kingdom will also cancel on them when the war is over. Greenlanders have been less clear in their intentions, although they are fighting on the C&G side of the war, and even arguably Polar's closest allies in STA are fighting on the other side, although there is little indication that that treaty will go. Polar has already partially lost NSO to the ex-Hegemony side, although their re-entrance to the war on behalf of NSO means that that bond will remain in its current state.
So on a conservative estimate, Polaris will have lost two thirds of the treaties that provide leverage on the emerging Supergrievances power cluster, and around one third of its strength assuming it does not achieve a quick peace. An unfortunate precedent set by this result is that interference in the name of justice is hugely damaging and has you cast as an aggressor, so it is unlikely that Polaris or any other alliance will seriously consider it in future – allowing unjust behaviour to proliferate as long as the bullies have sufficient backing.
A naive assessment of all the mutual destruction would cast the NPO as the winners, and indeed that sentiment is quite common. But I would say that it is not that simple; NPO are not losing strength, true, but the alliances that they would be expected to share a power cluster with (IRON, NATO, TOOL, Purple and perhaps TOP) are all fighting, and all on what is almost certain to be the losing side. Pacifica will come out of terms strong and powerful, but the alliances it could call to its side will be weakened and provide much less protection for her.
One major trend that's become clear in the last two incidents (the New Year non-war and this war) is that C&G and Superfriends are becoming closer. The 'Supergrievances' name, coined for the wartime coalition for the war that didn't happen, fairly describes that section of the web. The obvious impact of a prolonged war with TOP's nukes landing on C&G is to push this relationship strongly in favour of SF. C&G will no longer have the power or influence to maintain its position as a semi-independent centre of power, and the Supergrievances megabloc will be where they'll run to once the damage is done.
On the other side, the main casualty is Citadel, which will almost certainly dissociate entirely afterwards. Having already lost Grämlins in their mass cancellation spree, it now finds itself split between the two sides, with Umbrella, FOK and MHA fighting on the raiding side and TOP on the Polar side. This split, along with the inevitable decrease in TOP's strength, will at the very least render Citadel too small to project power, and more likely see it dissociate entirely, with TOP moving towards IRON and ex-Hegemony, Umbrella and Argent towards Supergrievances and FCC reverting to their previous independence. The Polar centre may also become so weak that it has to turn in with the Hegemony, though Polar's pride is likely to mean that they remain outside the power centres if they can't maintain their own.
Many alliances have found themselves pulled into this war by treaty ties (although few alliances have been legally mandated to enter, MDP level treaties provide strong political pressure to enter on the side of an ally) when they had no interest invested in either side. It is likely that several alliances without a primary bloc will severely rationalise their treaty ties, pursuing a more independent path, so as to avoid this type of situation in future. My own alliance, Viridia, is one of those in this position, along with Sparta, FOK, MHA and IRON – possibly the Citadel alliances as well if that bloc disintegrates.
In conclusion, we'll have a very different looking web at the end of this war. Instead of five discrete power centres, each with similar strength, we'll be left with two main ones (Supergrievances and a reconstituted bloc of Hegemony remnants plus TOP, essentially the Coincidence Coalition from the TPF non-war), plus a weak third centred around a weakened Polar. With most of the Coincidence alliances weakened by war and surrender terms, Supergrievances (with SF in charge) will have the upper hand, but not sufficiently so to be truly a new hegemony. Expect a polarisation of politics into 'them and us', with the third parties (including Polar and the more independently minded alliances) being marginalised if they refuse to choose a side, and possibly a repeat war (similar to GW3) pushed by Supergrievances in order to cement its hegemony and take control of the world.
Of course we must all be vigilant against the emergence of a new all-powerful hegemony, particularly one with some of the alliances that will be prominent within it. This war will not bring us to that point, but the cold war that follows it may well do so if we are not on our guard against it.