One Other Law Of Land Warfare

Something that occurred to me while I was looking at the Hague Conventions the other day. When I was but a young lad, even before they covered the Geneva Conventions, the Army taught all of us what was called the First Law of Land Warfare.

What can be seen can be hit.
What can be hit can be killed.

By extension, it would seem this reduces to 'What can be seen can be killed.' I suppose this makes How Not To Be Seen even more important. The Army was trying to make a point about cover and concealment, whereas I have no point whatsoever. Just an odd little tidbit I remembered.