Incidentally, I should take the time to post a couple more of my notes while I still remember this TL well. First, here's the rough 2010 population in OTL of the nations/regions described. In other words, this is what the modern-day population would be if this TL had no effects on immigration patterns and growth rates ... which, of course, is not the case. So think of this as an anchor while you try to figure out what the grand sweep of those changes would be.
- USA: 205 million
- DSA minus Caribbean: 130
- Caribbean: 40 (The Caribbean islands seem to be trending towards being a Dominion separate from the DSA)
- Mexico: 145
- Brazil: 95
- Ex-Brazilian breakaways: 95
- Granada: 90
- UPSA: 90
I'm sure some of this is Glen's planning and some is serendipity, but I am very impressed at the parity and balance in the Alt-Americas. These are all nicely sized nations, and the possibility of one nation dominating another will depend far more on technology, economy, and culture than it will on sheer size.