NCR would have eatten jacobstown, like they were already planning to when you stumble on it as the courier. also the only true ending is elijah gasses the whole mojave
[spoiler for the show] what do you mean it doesnt make sens for the ncr to collapse because of a single nuke. What's that? you mean to tell me that the biggest ncr threat was the ncr itself and its imperialistic nature? You mean to tell ME?! the all powerful todd howard that it would make for a way more poetic ending if the ncr collapsed due to no one's fault but it's own hubris? HELL NO of course a single nuke on the capital would collapse the entire chain of command, there couldn't possibly be any contingencies incase something like this were to happen... of course a single overseer would be able to find a nuke and launch it at shady sand... nevermind the fact that if there were any nukes in the vicinity the ncr would have claimed it and that the divide would be the only place that a intact nuke could be found... just ignore the flaws of logic or the fact that we never should've messed with already established cannon.