Write short notes on (a) Accretion and avulsion

The state — international law's original and primary subject (the system was built for states — Unit 1's Westphalian matrix). The criteria of statehood — the Montevideo Convention, 1933, Article 1 (the canonical quartet): (1) a permanent population; (2) a defined territory (defined — not surveyed: disputed boundaries do not destroy statehood); (3) a government (effective control — the decisive criterion); (4) the capacity to enter into relations with other states (independence — external sovereignty). Doctrinal refinements: effectiveness vs. legality — the classical criterion is effective control, but illegal origins (aggression, apartheid) taint statehood (ex injuria jus non oritur; Rhodesia's 1965 UDI and the 2014 Crimea annexation's collective non-recognition); self-determination producing states whose birth is legality's triumph over effectiveness; failing states (Somalia's decade) as the criteria's stress cases — practice maintaining legal continuity while effectiveness collapses. Sovereignty — the state's legal signature: Internal sovereignty: supremacy over all persons and things within the territory — the law- making monopoly (subject to international obligations); External sovereignty: independence — no external authority above the state (par in parem non habet imperium); the capacity to conduct foreign relations, conclude treaties, and be equal in law with every other state however powerful; The qualifications modern law imposes: sovereignty is no longer licence — the force- prohibition (Unit 11), human-rights obligations, and interdependence's treaties (WTO, environment)…