>The US isn't going to risk a dam flooding or a long term grid failure over a distant minor ally.

People are irrational. For the sake of transgressing a minor boundary, wars have occurred, even if the boundary has no strategic value. Suppose there are patrols into barren hinterland, that could still cause a war, even though the lands could not support permanent habitation.

It is theorized that Germany started WWI because of growing popular support for the socialist party.