Hold the phone, you forgot to tell us that you had already lost the game by UN vote.
I went ahead and finished, what I thought was a domination win and boom the game did not end. So anyway you could have in fact run over them, they never were even a threat, just some annoying nukes on a few occasions and lots of global warming (I helped).
Many times they had one or two nukes and would hit 1000%, oh well. I sent about 300 nikes before I finally sent in the armies (~15). Never did use all the MA's you already had.
I see you had the leader in 1812, why did you not use him for an army? That would have sped up things a lot. So many cities, I figured you had the academy built, but I just could not find it. Turns out you never had an army.
If you want to have scores of cities and play into the modern ages, you need lots of slaves to handle the pollution and any fallout. You need to trim the ai to lower it global warming tendencies, if you want to avoid the work.
Good luck