11.2 Jus ad Bellum, Jus in Bello and Jus contra Bellum

The conceptual spine: (1) jus ad bellum — the law governing the resort to force (the just-war criteria: just cause, legitimate authority, last resort, proportionality of ends; modernly the Charter's prohibition + self-defence); (2) jus in bello — the law governing the conduct of hostilities (Unit 12's humanitarian law), applicable equally to both sides regardless of who started (the separation principle — the aggressor's soldiers are lawful combatants; the just side may not violate the laws with impunity: the twentieth century's hardest-won clarity); (3) jus contra bellum — the Charter's law against war: the prohibition regime + collective security + dispute settlement (Unit 10) — no longer regulating war's how or why but excluding it. The core text — Article 2(4): "All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any State, or in any other manner inconsistent with the Purposes of the United Nations." The elements: force (armed force — Nicaragua: economic/political coercion excluded); threat as well as use; the protected interests (read as the situations protected, not loopholes); the Purposes catch- all. The exceptions' closed architecture: (1) self-defence (Article 51); (2) collective security (Chapter VII); (3) the debatable residual — invitation (below) and humanitarian intervention's contested claim.