I’ve been talking to some engineers this week who design harbours. There is a fashion for vaguely annular ones, apparently, among the super-rich.
When they have walls (ie they aren’t just jetties), wave action is intensified within them (acting as lenses) and the boats on the inside end up crashing up and down on 10m waves.
Today’s invention is to make use of this by designing a harbour which can accommodate larger vessels. This would have a conical underwater base into which debris from the ships would fall after waves had smashed them together for a few days. The cone could be dragged onshore using a winch and the contents reprocessed to smaller scales.
The noise would be dreadful, but this would eventually reduce even ships to fragments in a lower cost way than having people with blowtorches do the job in months.