Navarro could only hold off the outside world for so long. Without the rig to resupply them the base would fall maybe not right away but over a couple of years it could. The partols we encounter in Fallout 2 are people from the rig not Navarro at least most of them would be. The base itself only had what a dozen or so PA troops?. Most of the Enclave would have gone East. Also Navarro is to far away to be in Vegas. If the Enclave still controls it they would be busy defending it from other powerful factions to be going to Vegas.
Like others have said I don't think they should be back and after two major defeats they are done as a powerful faction. They could be in New Vegas as a small group or just Ex-Enclave mercs. I just don't want them as a powerful faction or even as a competent small faction trying to rebuild with another president.
I like to think that the Enclave are done in the West and the title of "president" is used as a boogeyman to frighten children.
I don't expect them to be in FO:NV. 4 years is not long enough for them to have recovered from the East Coast failure.
I think you are doubting Navarro's power though. If you look at the BoS in Fallout 1, they had about the same amount of men at base. Just look at the damage the BoS did to the NCR during their war, with even less advanced tech than the Enclave had. Now, add even more men for the Enclave (the patrolmen around Navarro), and you have a powerful mix.
Also take into consideration the fact that the NCR and BoS where at war. Both sides lost a lot of men. Both sides have Low Moral. Then expecting them to attack the Navarro? The BoS have inferior tech (and post FO2, less men), and the NCR lost SOOO many troops to the BoS (who where able to fight back due to their tech thats less advanced than the Enclave's). The Enclave at Navarro is still more powerful than the both of them.
And they (Enclave) would run out of supplies like you said. But, why wouldn't they do what the BoS did: Trade tech for supplies?
Now add in what I said a few posts ago:
Another factor to take into regard is the fact that the Enclave could have had multiple bases. In FO2, if you are at the oil rig, on the same level as the president, the room right of the presidential office there is a map of the world. On that map there are 2 dots in California, 1 on the East Coast near DC, and many more scattered round the USA. I dont think they represent the Vaults, because there is only 1 on the East Coast near DC (while there are many vaults in FO3). If you where to look at them as Enclave bases, it would make out perfectly. 2 in Cali (Oil Rig and Navarro) and 1 on the East Coast (Raven Rock). It would not make much since either, having vault experiments on a map where you make you major strategic decisions. It would be more logical to have that information in a lab or observation terminal.
ANOTHER question to raise is: If they where sooo weak after FO2, how did they manage to create that mobile crawler + get hold of all those Vertibirds that we see flying out of RR after it is blown up? They either are not as weak as we think at Navarro or they had more bases scattered through the former nation. They even managed to create new and better Power Armor (meaning they have factories somewhere). Otherwise, it would be near impossible for them to get that equipment and manage a trek across the U.S.. It is even said that the Oil rig was only the HQ of the Enclave. That does not mean it is the only major base.
If, like you say, the MQ ending is only following the "good" trail, that would not eliminate the Enclave. Yes, it would weaken them, but they must surely still have more bases and soldiers elsewhere.
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But the Germans didn't find out that Hitler wasn't real. When your country or faction espouses a return to a pure humanity and the ideals of America before the Great War, discovering your figurehead isn't even a human being is almost like a third defeat all at once.
And I do believe the Enclave will eventually bounce back, but it will never be the same.
Exactly. A further hindrance to the growth and recovery of the Enclave is that the native population no longer trusts them, and even fears them. After all the propaganda and effort to sway the populace to their support on the East coast, only to come in and attack settlements and wastelanders, means most people are going to warn their children about ever trusting something called the Enclave. One could even theorize that a name change would be required to make headway with their plans and recovery in the future. After all, the Germans are the same people and country, but they certainly don't call themselves Nazis any longer, and have actively distanced themselves from the name and its associations. One could see the Enclave doing something similar (and maybe changing their tactics to not include genocide).
But does the Enclave need the support of the populace? Assuming there are no other bases with active Enclave in them, the Enclave archives would have all the information on all pre-war military facilities. What would stop the survivors from finding one and taking it back over, fortifying it, and using it as a new HQ? They would know what was dangerous and what was not through the eye bots reports of the wasteland.
I do agree that the Enclave won't reach the power they had in FO2 though. Not for a very long time.