As far a as I know, its like billy says.
Lightning works its own way - so each strike or near miss will damage in a different way. Cant experiment with it to find out.
Steel boats will act like a faaday cage, but an antenna will bring the current down into the inside. I heard to disconnect the antenna if in a storm ** defeats the purpose doesnt it!!)
Us sailboats do have an aluminium (or sometimes wooden) lightning rod pointing up.