There are cases where this would definitely be the right thing to do. We don't have that feature right now, but there are two common conditions with different best solutions:

1) If the tribe is very personal to someone and they were really the sole source of information and content, then in general they should be able to decide they don't want it to persist. The best way to do that now is to delete all the members (but NOT you, the moderator, please) then make the Tribe private. You can then remove it from your home page and it becomes a ghost in the database. We can not now, but we will be able to flush old ghosts out of the database.

2) If the tribe was active at one point and of more than purely personal interest, the best course of action is for the moderator to abdicate and invite another member to moderate. If more than one person would like to, there's an election mechanism we can respond to.

Both processes need better support in the interface.