I'm playing with the 1.1patch, so the following may simply be a result of the Beta status of the patch. I also only recently started incorporating military starbases into my strategy so have no point of comparison pre-beta.
I build a military starbase and add the basic starship assist defence bonus (1/1/1) and yet all my ships within it's radius still have no defence. Offensive modules built on the starbase affect ships as I expected, so I'm not sure what I'm doing wrong.
I have also seen enemy ships with 1/1/1 defences in and around their home planets, so either the AI is building ships with radically different priorities in the new patch, or one of their military starbases was applying the defensive bonus correctly.
If it is the case that a ship already needs defence in a certain area for bonuses to take effect then defesive modules seem rather underpowered given that offensive module bonuses apply even to types of attack the ship doesn't start with.
I am confused. Help please!