"Navies other than the US are just useful objects of target practice. The US technological lead in this big. Heck, even China's desire to control the Taiwan straits is just a fantasy, and will be for the forseeable future."
I dont know what you mean by that. What has US technological lead got to do with India strengthening its navy. So if US technological lead makes it overwhelmingly strong still thats no reason why India (or for that matter countries like Japan and Australia) shouldn't be having a navy. Just because the US is far too strong does not mean that its a waste of time and money for others to guard once border, shipping lanes, economic zone and protect onself from enemies.
I am unaware of any navy going about harrassing others without US permission. The tubs are a joke.
Their tubs can float anywhere they want. They just won't do anything hostile, because if they do, they won't float anymore.
Get real -- do you really want Japan, Taiwan, S. Korea, Australia, The UK, India and other US allies and friends to disband their navies and let the USN patrol their waters? What about the cost of that?