Yes, I know nukes will generally not explode when hit, and the high explosives in them will not make a really big bLast.
For storytelling purposes, I consider the warheads to be armed, and hair triggered
. So the missiles explode just before PDCs would have finished 'em off, in the hopes of doing splash damage.
I should also note that I never said that I was going to set the damage from an exploding missile launcher really high. 75 damage would be plenty to account for fuel stores in the launch bay.
Still, the biggest use for this will be in the Cobalt warheads
If you have a ramming ship, one small hit could trigger a chain reaction and blow your ship to smitherines