Instead of "“How do I maintain authority over my security force after the event?" How about
How can I protect the most possible people and build the best functioning society post collapse to ensure the survival of myself and my progeny.
This gives the lie to the idea that the captains of industry are great men they aren't great men they are toads towering above our lives and yet beneath our contempt.
How about just selling basic farming equipment to the new communities that arise from the ashes?
Quality gardening tools will go a long way in the post-apocalyptic world, I think. And doing so is far less likely to earn you a place in the guillotine, than being a bunker-resource hoarder.
How can I protect the most possible people and build the best functioning society post collapse to ensure the survival of myself and my progeny.
This gives the lie to the idea that the captains of industry are great men they aren't great men they are toads towering above our lives and yet beneath our contempt.