sorry, i was mostly referring to MP. the AI being incompetent at defending is an AI thing.Its not hard at all to take in vanilla. As someone was trying to explain above because it's one provence your divisions cant retreat to regain org so they just get deleted when they have no org. You can literally take Gibraltar with 10 width cavalry naval invasions with zero airsupport if you want.
You simply constantly have a naval invasion going and it prevents the defenders from ever regaining org. I have seen mods divide Gibraltar into THREE tiles two coastal and one inland just so there was someplace the divisions could reorg. Hoi 4 mechanics make any 1 Provence island a death trap.....
in MP when you invade a competent UK will just put their surface fleet out (maybe in a few separate groups, especially if Italy's been neutered) and kill all of the invaders, regardless of whether or not the enemy has naval superiority, and sink them. and of course the enemy getting naval superiority in the first place is very uncommon too.
it can only really be taken if the UK let their navy die trying to save Africa AND the Allies traded air badly with the Axis/lost French airbases/etc.