320 A Positive Century (1815–1914)states over the previous two centuries. It also broke some new ground,
chiefl y in its fi rm statement that privateering was abolished. Th e declaration
was highly successful in attracting support from other countries around the
world, attaining over forty ratifi cations. Signifi cantly, the parties included
Britain, which had previously resisted the “free ships– free goods” principle
(on the ground that it unduly restricted the employment of British naval
power).
Soon aft er this, there were some important multilateral conventions on
war matters. Th ese marked the fi rst concrete steps in fulfi llment of Vattel’s
vision of a code of conduct that would govern warfare— and put an end to
the reliance on the principle of military necessity as the sole governing prin-
ciple in the laws of war. Th e fi rst of these initiatives was a convention in
1864, dra ft ed by the newly founded International Committee of the Red
Cross. It provided for the immunity of medical personnel on the battlefi eld
from attack. In 1868, some additional articles were concluded, further ex-
tending the protection. Th en, in 1906, protection was extended to wounded
soldiers themselves, by imposing onto captor states a duty to care for
wounded enemy troops.
An international conference in St. Petersburg in 1868 produced another
interesting innovation. Th is was an international agreement on the prohibi-
tion of a weapon— something last done (or attempted) in 1139, when the
Second Lateran Council prohibited the use of crossbows (against Chris-
tians). Th e concern on this occasion was the possible development of ex-
ploding bullets. To forestall such a possibility, the conference issued a decla-
ration, in which all parties promised not to deploy such a weapon.
More important, by far, than this prohibition against exploding bullets
was a statement, in the preamble of the Declaration of St. Petersburg, of two
very general principles that were— and remain— of cardinal importance for
the laws of war. One was a general condemnation of “arms which uselessly
aggravate the suff erings of disabled men, or render their death inevitable.”
Th e other was a similarly general statement that “the only legitimate object
which States should endeavor to accomplish during war is to weaken the
military forces of the enemy.” Th at meant that, as a matter of fundamental
principle, war is to be waged only against the armed forces of the opposing
side and not against civilian populations. Th is continues, to the present day,
to be a cornerstone of the laws of war— if not always, sadly, of the practice.