Ah, so now I see why I asked that Q in my previous post.
Two pieces of info, from your post, I didn't previously know :
1. India claimed (claims) 250 n.mi. extra EEZ (which is legal as per UNCLOS; extension of continental shelf)
2. India treats the 450 n.mi. (200+250) as TW.
I'm okay with that considering that many countries do that with some countries claiming entire seas.
Besides, as you say, legality is, well, not a concrete term.
PS: I think you meant 12 n.mi. as TW, not 20 mi.
Nah, I meant 20 miles.
There are certain nuances and technicalities within that so it eventually ends up being 20 miles because if there's a submerged continental reef, then shall we consider it as deep sea or shallow waters and apply rules accordingly? and therefore an exception has been made for shallow reefs, which includes submerged reefs too, I think. There is a whole chapter on how to handle territorial claims of nations which have archipelago configurations. Shall it be treated as de facto land and given its own TW and EEZ or shall it be granted only a nominal TW? and so, in most cases they end up creating an exception called archipelago baseline (AB). And most of the times AB + TW roughly ends up being 20 miles. Because of the way ocean beds are formed, most of the times they are uneven and the dichotomy between land and sea isn't well defined so more than 95% of all land-sea borders have a natural continental shelf which ends up extending the AB. So the arithmetic ends up with supplementary TW extension from the legal 12 miles to de facto 20 miles. The earlier diagram was just a make shift one for school children, this one explains it better. The deeper interest you take in it, the more complicated and interesting it gets.
Consider all these rules, exceptions, islands, just to define a non disputed boundary. Imagine how complicated it gets when there are conflicting or overlapping claims? Our conflict with Myanmar and Bangladesh is one such example which will make anyone pull their hair.
The same game is being played out in Souch China Sea where China is treating the continental shelf as de facto land and then extending their argument from there to claim full sovereignty over those grey areas. Legally, there's no right or wrong and so if you observe carefully, no American propaganda channel (colloquially known as 'media') ever calls it a legal dispute. The only notion they keep harping on is "this behavior might lead to conflict", basically taking not a legal stance, but an moral one. It is a cryptic way of saying "we will beat you if you try to claim the grey area which we have illegally monopolized until now". Morally and dispassionately speaking, China has a greater right over that area than a foreign power from another continent, but because China has been so rude to its neighbors, they are happy to see China bleed. Compare China's territorial claims to the one which Japan made, in cohorts with their pimp, the USA, and China's transgressions seem trivial in comparison. Since claims over territorial waters extend themselves into Air Defense Identification Zone (ADIZ) protocols, it impacts the control of airspace as well.
The US allowed a large overlapping claim to arise between China and Japan be allowing (read : encouraging) Japan to redefine the territorial claims over Senkaku Islands. In fact, it was this imperialist aggression which provoked China to open up another front and that is how the South China Sea dispute came into being as a response to US douchbaggery, just like the Syria and Ukraine came into being, not the other way round, as the American media claims. They are trying to put the horse before the cart and sell snake oil to the world if they claim that intervention in Indian Ocean, SCS, Ukraine, Syria has got anything to do with freedoms and human rights. They are the one creating the problems by 'challenging' countries thousands of miles away from their continent.
Essentially all territorial water disputes until now followed the theme of "this land belongs to us therefore the adjacent waters belong to us", the paradigm shift that China has brought to the equation is "this water belongs to us, therefore the land belongs to us, therefore more water belongs to us". 'Land' here is loosely taken to assume continental reef, and they have dumped sand on the reef and pulled the reefs out of the legal grey area and into firm footing (pun intended) and as a corollary, extended their territorial water and ADIZ. Japan did exactly that, but American propaganda will never tell that side of the story.
Basically long story short, 'Freedom of Navigation' is to capitalism what 'Freedom of Religion' is to Christianity. The former is meant to extend their capitalist hegemony and the latter is meant to extend their Christian hegemony, they are misnomers which have nothing to do with the freedom of people who don't fall in the aforementioned coveted categories.
