Peak oil has occurred, daily life has reverted back to localized communities and localized production.
Few large cities/settlements remain
Mass exoduses from former petro-states to the west results in conflict
Shit has gone on for so long that modern weapons are either running out of ammunition, or being lost due to attrition (humor me on this one! Apply copious amounts of bullshitium). Black powder weapons are now being used.
Personal communication devices and NODs no longer work due to lack of batteries or the ability to charge them (not sure if this is accurate or not…)
How does one fight a war in this scenario? I have heard some on craptube say that “armies would revert back to mass formations and lines of battle” but that seems idiotic and suicidal. Fire and maneuver with muzzle loaders or bolt action rifles with black powder loads might also be problematic.
And what would be the most advanced weapon that could use black powder? Rifled muskets? Bolt action rifles? I personally suspect that semi/full-autos are out of the question - the fouling from the black powder would foul up the action. You might get a couple of shots off but then it would need to be cleaned.
Why would black powder weapons be used in a such a scenario? It’s not like black powder manufacturing is all that widely different from smokeless powder manufacturing, and if your excuse is brass shortage then why not shotgun shells or even bootleg caseless. And even, ignoring that, if we did go back to blackpowder, we wouldn’t be using muzzle loaders, we’d go to paper cartridges & modernly enhanced rocket balls in breech/tube loaders.
Political correctness would die. Only the strong survive… those who don’t need free stuff given to them. Industrious men would rebuild. The details of the rebuilding successes would be as varied as the men behind them. Men and women… btw.
Black powder would be useful for localized production. While smokeless powders could still be made I imagine obtaining and transporting the chemicals/materials needed to make them might make the cost prohibitive. Or at the very least make it an expensive thing that only the special forces or their equivalents get to use. Of course, I could be wrong. And I will admit I am pretty ignorant when it comes to these matters and have a lot to learn.
A brass shortage might not be the issue - it might be that there is not enough electricity to run the machines to make brass sheets. Unless there is a low tech solution, or a given factory/community/whatever has access to a renewable source of energy like hydroelectric, geothermal, etc.
Again I know very little about this topic, so this could be complete bullshit on my part.
All that’s gonna happens transport wise is the massive switch to electric power that the car industry (and not the oil industry) has been trying to avoid for a century (did you know electric cars are OLDER than internal combustion engine cars? And that they had some going over 100 km/h in 1899?)
You can thank both Germans and Americans for screwing everyone up and burning the finite reserve oil (a.k.a. the material of God, that can be recombined in hundreds of thousands of fashions, the dream of all alchemists) for over a century instead of using it to better mankind and improve life in the long run.
Older forms of smokeless powder exist that are just as easy to manufacture without electricity as black powder, and while not as effective as true modern powder are still miles above bp. I.e cordite