But that requires a huge and expensive fleet, plus islands like Sardinia and Corsica are close enough to land that you can make boats, load them up and ditch the soldiers on the island in one go....
Maybe I didn't quite explain this right;
It looks a whole lot like the computer sees islands as sharing a border with them, so they'll attack happily. A land province the same distance away that is attached to the same land mass the computer doesn't see as sharing a border so it won't attack. The computer doesn't sail an army along the coast of the mainland to assault a province further down. For Example as the English the Danes will happily sail armies to attack London and Nottingham, but they won't go after Caen.
Islands now seem to act as provinces that shares vast numbers or borders, hence making them a pain to defend and inciting more wars than you can throw a Javalin at.
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