International Legal Evangelism: Intelligence, Reconnaissance & Missions

another, and that choice may be guided by some independent sense of the moral
quality of the consensus.
In a stylized case, we may find that 45% of nations allow a successful siege
to end in the slaughter of a city’s defenders if they were offered, at a late stage in
the siege, an opportunity to surrender the city with impunity, while 40% of
countries may in these circumstances prohibit the slaughter of defenders who ask
for quarter after the city’s walls have been breached. Both consensuses are partial.
But we may regard the latter as the law of nations, even though it is numerically
inferior on account of its embodying a morally superior standard. We trade off the
extent of support against the moral quality of the position. At an extremity, of
course, this becomes pure natural law moralizing. But in the stylized case I have
mentioned, it is more like Rawlsian reflective equilibrium or Dworkinian
interpretation of global practice. 145
That’s Gentili in the late 16 th century. Much the same is true of Hugo
Grotius, writing a generation later. Grotius too made progress in the international
realm not by asking (as a moral philosopher might) what the natural law values and
principles are, but by asking what people have taken them to be and what they
have done in the world with the answers that they happen to have come up with.
He too was interested in the way something like positive law emerged from the
practice of nations, more particularly from those aspects of national practice where
nations could be seen to have been asking themselves scrupulously and honorably
what is right and wrong (so far as war and peace are concerned). True, his
understanding of all this was leavened by his own strong first-order moral sense
(his own direct natural law enquiries); but it was never dominated by that sense to
the exclusion of any consideration of actual practice and custom. Grotius took
practice, custom, and opinion seriously in the way that a pure natural law enquiry
cannot. And for that reason he was far better positioned to understand, from a
natural law point of view, how positive law might come into existence and flourish
in this realm.
We can reflect on all this from a jurisprudential, a moral, and a theological
perspective. Jurisprudentially, I come back to something I said in Lecture One.
Sometimes when humans are at their most ferocious and hard-hearted, they still
manage—perhaps in spite of themselves—to pay homage in their practice to
strands of normativity and restraint. It was, I said, the mission of thinkers like
Grotius and Gentili to sift through the historical evidence of war-mongering to
discern, recover, and make articulate as law, elements of restraint that were there
anyway—half-hearted, haphazard, no doubt, impure, certainly, and sometimes
insincere. Still that is how legality enters the world.
145 Rawls, TJ, __ and Dworkin, Law’s Empire, __.
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