I still say the USA will expand a bit, but not to the originals size. Not too big either. Closer to it's current size.

The Celtic Alliance will join with the OBN and become the dominant power of Europe

I believe the CA is already part of the OBN? Could be mistaken though.

Only part of the west coast that is even sympathetic to the idea of joining the new USA is the new California Republic - and even that is a near-fantasy at best.

As for others, there are several states on the continent that, should it become feasible, might do it. Problem there is, they are all very isolated geographically from the new USA. Nearest one that would definitely be willing is the Hannibal government. Stillwater might be interested, but seems to be gravitating towards Texas.

It's not going to expand much - and virtually all of that will be into unclaimed lands.

CA is not part of the OBN - nor would it join it.

I meant the other way around the obn nations will eventually join the CA and become the dominant power. 

That is kinda what I meant about USA....

Spartian, then what you meant and said are not the same things.

Lewody, two very different nation-groups. Not happening.

Fair enough.

I think the SAC and CANZ won't got to war. Europe will get reclaimed by the various survivour nations (eventually), same with the US and China. REMUNDO might become something like OTL internet.

Yea Europe is most definately heading for nation-states reclaiming lands. Some sort of either alliance or two split groups may occur in Germany as the nations expand and come into contact with each other.

The OBN will most likely enter into a Federation along the same lines as Germany did in 1871. So most of the states keep their monarchies, but an effort is made to find the person with the purest bloodline in the Royal Family and offer them the postion of King/Queen. Celtic Alliance will remain a rival - although probably no war will erupt. New Britain will probably look to get involed in "Old-British" politics, probably becoming observer member in economic unions and things and would look to retain some sort of link/influence with the nations.

I'd reckon the Nordic Union will grow in power and one language will gain influence over the others - probably Swedish and become the main lingua franca of the group. I think it may also allow more nations to enter it and reform many elements such as military and economy. And infrastructure would most defo be upgraded between the states, perhaps like a major motorway being built to connect all the states or something.

I reckon ANZC superiority will remain throughout most of the century - with SAC playing the role of China trying to catch the US. But in their case, the SAC will eventually reach ANZC and perhaps overtake them.

Nah, the UIP will survive. And eventually an identity will be created for the group once more, when things stabilise and industry recovers in the nation.

China, well I do not reckon that the PRC will collapse or anything. I would most likely think a coalition against them would eventually come into being, RoC-led. It would be a bloody war and opening battles major, but once the first battles are over, the PRC would rapidly fall.

Yea, REMUNDO will most likely become that, although to get to OTL internet standards will take anywhere from 15-30 years. And the SAC will play the same role in internet creation that America and Britain played (mainly America).