Only the owner (as far as I know) can protect assets. The protected assets are then unable to be made-over (if I remember correctly) unless they are un-protected first. It is a one time fee (unless you choose to un-protect them in which case you must pay again.)
Did they re-add that? When it was first released, the leader could protect, but not unprotect (only the owner could do that). Then they made it so only the owner could do either, which was annoying.