For Mexico, this was not, by any means, the proper interpretation of the
self-defence exception. Indeed, he argued, “[t]his principle [of
self-defence] would never have been allowed, were it not, as it is, founded in justice and reason; where it not like all the other principles, together composing the law of nations, derived from the natural law”. Thus, he continued, the right to
self-defence “fixes upon us the obligation of preserving and defending ourselves” but, at the same time, “prohibits us from so doing to the evident injury of a...