>>16709637Sealand had the advantage of having a court order protecting it and of course the rather big advantage that it was built by competent military engineers to withstand attack. Minerva was a bunch of sand piled on top of an atoll. That made them very vulnerable to attack. The King of Tonga didn't care to check with a judge, he just sent out troops to invade.
The economy, if they'd lasted long enough to build up a solid island, was to be based on tourism, fishing (cover stories), but really was going to be drug manufacturing, off shore accounting, and minting gold and silver coins.