Personally I leave it set to depth below keel, to which I add 1.5 metres for actual depth. There is a special corner of hell reserved for the person who then reset it to actual depth and did not tell me or put it back again! Fortunately I had already slowed right down thinking ... surprised there's this much water here as we came to a sudden stop.
Since lateral means side, multilateral means basically many-sided. The philosophy of multilateralism claims that the best solutions generally result when as many of the world's nations as possible are involved in discussions, and multilateralists often favor strengthening the United Nations.
Unilateralism is a neologism which is already in common use; it was coined to be an antonym for multilateralism, which is the doctrine which asserts the benefits of participation from as many parties as possible. The two terms together can refer to differences in foreign policy approached to international problems.