Chapter 4 turns to the application of use force principles in the maritime zones under the law of the sea. Territorial and internal waters are subject to sovereign national jurisdiction and are the most restrictive in terms of the ability of warships to use force in self-defence. Conversely, a warship which does not respect the sovereignty of the coastal state does not necessarily pose a lethal threat. The coastal state should distinguish between threats to sovereignty and threats to life – non-lethal threats demand no more than non-lethal responses. The Swedish response to submerged contacts in the 1980s is an example of state practice, and the South China Sea Arbitral Award provides some guidance as to the law.