India has pretty much the same perspective about megadeaths as the A4. They also find the Chinese to be somewhat worrisome, especially since the spend tons of money rescuing people trying to flee over the highest mountain rang, in the world, in winter, trying to get away,You can’t say it supports the right to self determination and then in the same breath have it prevent the liberal democratic states of Germany from unifying pick one or the other.
As for the ban on space you say how many otl nations can do it yes space is expensive but you also said they are all richer and they are more technologically advanced since they were able to put rail guns in space and bomb Stettin.
But technology is not static usually so eventually for economic resource extraction people would set up space colonies or just to deal with over crowding they’d make space colonies the A4 stop everyone except the Anglo nations from leaving earth which is a slow genocide. It’s basically eventually going to lead to all humans except those who are Anglo descendants to be left on what is effectively a reservation, I’m surprised India hasn’t allied with China to start a world war to stop the A4 from banning everyone else from space and dominating humanity forever.
I really don't go too far into defending the A4. The concept is, IMO relatively sound, but they are suffering from a a case of National PTSD, and have built their entire international policy around it. The worst part, and they don't really understand this, is that the minute they stop being the 900 pound gorilla all the death and destruction that they have suppressed is going to spring back into plase with a whiplash effect. All the leaders who want to get more power, or more money, or start their own empires are going to start back up and since the A4 has made it possible for countries to have fairly small armed forces overall, when the backlash happens a lots of countries are going to get rolled. It would likely take a couple centuries to really get past that, and it is hard to imagine that sort of time frame is going to be possible.