Legitimate use of military force against state-sponsored - Air University

await the arrival on scene of an armed aircraft, provided that aircraft were sent with due
dispatch. 76
Last Resort
Article 2(3) mandates that states “settle their international disputes by peaceful means in
such a manner that international peace and security, and justice, are not endangered.” Article 33
of the Charter requires that “the parties to a dispute, the continuance of which is likely to
endanger the maintenance of international peace and security, shall first of all, seek a solution
[by] peaceful means.” 77 These obligations require states to exhaust peaceful means before
resorting to self-defense. In the words of Rutgers University professor of law Tom J. Farer,
“there must not be alternative means of protection.” 78
The state facing harm does not need to exhaust peaceful means of settlement if
undertaking such efforts will prove fruitless. Also, if a state is under attack, it then has the right
to respond with force to meet force in self-defense. If an armed attack is in progress or imminent,
then the situation may preclude seeking peaceful settlement. But an entirely different situation
prevails if the armed attack has occurred and no future attack is imminent. 79 Use of force is not
required to defend against further armed attack as no such threat exists any longer.
Necessity of Response
Many writers see necessity as a requirement for exercising self-defense. 80 In reality
necessity is nothing more than a combination of elements previously discussed. Necessity arises
when factors of time and absence of other effective remedies merge. Necessity has been
described as “great and immediate,” “direct and immediate,” “compelling and instant,” and
“irreparable and imminent.” 81 Schachter sees necessity in this way:
The requirement of “necessity” for self-defense is not controversial as a general
proposition. However, its application in concrete cases requires assessments of the
facts and intentions which in turn involve diverse perceptions. The subjectivity of
such judgments may be seen as reducing the legal value of the requirement. This
may well be so but it should not lead to the conclusion that a judgment of
necessity is entirely subjective. A case of self-defense is not persuasive either on
the political or legal level unless a reasonable basis of necessity is perceived.” 82
As preconditions of necessity, Schachter finds that there must be both an imminent danger and
no other available peaceful solution. 83 If either does not exist, then neither does necessity. One
might also conclude that the primary thrust of the Caroline test is necessity.
Proportionality of Response
Two kinds of proportionality are required. First, the response must be proportional to the
delict or wrong suffered. It would undoubtedly be disproportionate to invade and occupy large
portions of another state’s territory or indiscriminately and directly make its cities the object of