Does air attack against ground units damage org, or only strength?
Besides focusing on moving units, what's the difference between interdiction and ground attack? Does interdiction actually slow units down?
Yes both.
That's it, Interdiction chooses to target moving targets first, while ground attack tries to target static ground units first, but if they can't find the variety they are after then they hit the other and both do the the same damage as the other to their targets, no special slowing down of movement difference between them and the only consideration to how effective either mission is is any difference in their respective mission efficiencies that are researched in the Air Doctrines Tech tab page. Bear in mind that the AI only performs Ground Attack bombing missions AFAIK, so if you employ the AI to control your airforce then only bother with researching the Ground Attack mission efficiency one.