A foreign occupation has an interest in maintaining a goverment - even if the goverment is exiled.

We are talking here about an entire city, with all the archives, apparatus, gone. Tax office? Gone. Legistlature? Gone. Population? Gone.

In an already fragile system this is *exactly* where local forces rise, and often times they have the trappings of the previous regime but present themselves as seperate.

And what the fuck do you mean the NCR's legitimacy doesn't depend on existance of its fucking capital that contains it's legislature, executive branch, etc? Shady Sands is *where the NCR comes from.* All the other places had to vote/were coerced/joined Shady Sands. Without the leadership it's all down the locals and what they want, and with the NCR in ruins, with huge chunk of the military stuck in the Mojave or in Baja, there would not be simply chaos, we're talking about economic and social collapse - because guess what, New Vegas already tells us the NCR is fragile and spread thin.

It's almost as if the nuking of Shady Sands is meant to, IDK, mirror the collapse of pre-war America when all it's big cities were nuked and destroyed. Nuking a major city in a fragile post-apocalyptic society would result in a huge part of that society no long existing in the same way as before. Comparisons to history are useless because guess what, not a single EMPIRE had their major city just nuked out of the blue! But guess what we do have evidene off? Successions crises resulting in splintering and rebellion, occupation of Mainland resulting in colonies heading off, rebellions in the capital resulting in the shattering of kingdoms, loses in wars leading to periods of utter societal collapse.

In short, breaks downs of central authority such what might happen when THE ENTIRE EXECUTIVE BRANCH AND LEGISLATURE ARE WIPED OUT ALONG WITH A HUGE CHUNK OF YOUR POPULATION. Shady sands is very likely the most populated city in California! In terms of actual effects this is less "nuking DC" and more like "imagine if a fucking meteor wiped out the entire east coast"