My friends in Madagascar have rebelled against me, requiring me to naval invade them to take it back. I noticed their defense was really high because they had quickly built an army of trench infantry. They had no industry to speak of, so they were importing all their guns through the port in North Madagascar.
I should be able to render their army useless by cutting off their world market access. However, despite being at 100% blockade strength, the state has been at 100% world market access for months. And the tooltip seems to indicate that the blockade strength is increasing their world market access. This is sort of infuriating, so I'm hoping someone can either tell me what I'm doing wrong or confirm that this is a bug.
I should note that South Madagascar does not have a port, so they can't get world market access there anyway (and in any event, the game says South Madagascar has 25% world market access due to blockade).