Concentrating on just about anything during these days of the coronavirus, let alone academic writing, has been a trifle difficult these. A splendid new paper on Boer Bonds by Kim Oosterlinck and Marie Van Gansbeke (here) did, however, get me focused (for a bit). And that’s in part because their paper has potentially turned upside down what I thought was an established part of customary international law. That is, the law of