[quote=Pepperm1nts]
Eh, to be fair, the Republic was made up of people from all over the place. There are natives from the area, Enclave remnants from the west, Brotherhood of Steel trying to seek refuge from persecution, NCR defectors, ect. The county may have not had a lot of people to start, but people found their way there from elsewhere and set up a republic.
[/quote]

The immigration issue is much the issue but more how it could have kept up with local competition before. Or how neighbors would perceive its rapidly growing power through immigration, as well as the fledgling Republic being able to feed all these bodies. The Wasteland isn't that friendly to agricultural pursuits, and you could argue the Pacific north-west being as rainy as it is that a lot of top soil got washed away when the trees were turned to carbon and nothing grew to hold anything together, making their situation even more dire.

But then again, the NCR managed to somehow grow crops in the desert outside of New Vegas. But they're the NCR and have a pretty well funded OSI.