system
Given the following post, respond as if you're commenting on Reddit:
human
[Fallout New Vegas] The Courier goes for the Wild Card ending. How long could Vegas last?

Let's say that:

* The Courier had mostly positive relations with the NCR before betraying them.

* The Courier's killed Caesar.

* The Courier has gotten the Boomers, Enclave Remnants, and the FotA on their side, isolated the BoS, convinced the Great Khans to exile themselves, and has gained the loyalty of all the Strip Factions.

* Most towns love the Courier, and most raider factions have been exterminated. 

* Zion was defended and Salt-Upon-Wounds was spared.

* Old World Blues was completed with good karma.

* Dead Money was completed with all companions alive. Dog and God are merged. 

* Lonesome Road ended with Ulysses surviving and no Nukes firing.

Would Vegas Republic last long, or would it just survive until the Courier dies? Would they expand much and, if so, in what direction, and how successfully?
gpt
A generation, maybe two if the Courier is particularly good about setting up a power structure to survive their death post-game.  

Ultimately, a wildcard New Vegas has the same problem the Legion did.  It depends on a single phenomenally talented individual who is able to resolve all issues plaguing the region.  The disparate factions will band together so long as the Courier is still alive out of their respect for him, but they're all far too self-interested to remain together after he dies.  They don't share common values or a common culture, and none of them are individually powerful enough to dominate all the others.

The NCR *is* powerful enough to do that, impose its culture and system of government on the Mojave, and absorb it into the ever-growing blob that is the NCR.  It's probably not going to try to do that while the Courier is still alive, but it will be continually working behind the scenes to sabotage any attempt the Courier makes at building an enduring government that would be able to remain indefinitely independent.