Can drifting mines deny an area to shipping?

Can free-floating mines still be useful for sea denial?

Yes, particularly where the laying navy has no shipping of its own, although the earlier warning about drifting mines remains relevant.

Drifting mines can deny an area to an opponent even though their movement makes them dangerous to their own side. The follow-up assumes the laying navy has no shipping in that area. Australian interest in mines more generally is given as an example of the continuing attraction of sea denial.