I don't think the US would have flourished, or anything, but I've got confidence in its ability to at least survive, same for Mexico. And I may just be a suffering optimist, but I think that in an apocalyptic scenario the whites, Hispanics, and Indians of the Southwest would have been able to band together to rough it out, at the very least.
Also, why would the British Empire ever relocate to India? Even here, one of its white dominions, Australia (technically not a Dominion yet, but still), is alive and kicking. Why didn't Queen Victoria just move to Sydney, or Melbourne, or more likely Brisbane since it's closer to the equator than either of those other choices? Seems like Stirling needs to think about his scenarios more.
Even if the Federal Government got wiped out, that's not going to wipe out, say, Arkansas. Or Mississippi. Or Texas. And California collapsing into "wierdly theocratic city states" never made sense. There should at least be surviving state governments all over the place.
And the climate-shift plus tsunami shouldn't be enough to collapse Mexico, even if the tsunami could reach the coast.
Yeah, I'm with both of you guys. I admit I'm not well-versed in Peshawar Lancers, but I am put off by the amount of America-screws even if I like some of them.
It be interesting to explore what is left of the USA/America rumps in the South and West, or even a Second CSA to rise from the chaos, or a Western Republic.
It's the same in Doomsday 1983, with New Britain being based in South Africa while Australia and New Zealand forms one of the new major powers.
So yeah, more with North America and the British Empire in Australia would be cool to see.