I see the Vasudans as remarkably similiar to Terrans. Even the tech description describes a planet that could conceivably be close to ours. Hell, 98% of OUR water is undrinkable, even by human standards. Although Earth has 7 continents, dividing them into two large ones isn't really beyond the realm of imagination.
I find it hard to believe 100% of them are entirely unified. With a large population, you have to have some dissent.