Also, how do we define "massive"? In the case of China will it leave China Nuke-nude?
The reason the US gave up "Star Wars" was because of the sheer number of Soviet warheads, in the thousands that could be launched on the US with MIRVed missiles. Today's US ABM system is geared to guard against isolated missiles from "rogue states". In the Indian context, I would say that China is a rational actor who can be deterred...Pakistan is a non-rational actor only against India because of Partition and then Pakistan's second partition. If the objective of Indian ABM's is to defend against Pakistan, it is entirely feasible, because of the numbers involved and also because of geography wherein future long range Indian SAM's and AAM's could intercept in the boost phase.
Against China, and one should not look at today's China with its relatively limited 400-600 warhead count, but a China of the future which decides to expand its warhead count to a few thousand, the ABM system will never work. But then as I said, I believe China is and will continue to be a rational actor. The joker in the pack is proliferation from China to Pakistan, of MIRV technology, of N subs and SLBM's and any conceivable scenario in the future where Pakistan again gets "strategic depth" in Afghanistan.
But my point is that in an open ended escalation, the advantage of cost and strategy will lie with the attacker not with the ABM defence.
Added later: In the first Gulf War (1991), for every Scud fired by Iraq, the US responded with multiple Patriots i.e. often a battery of 4 missiles was fired to respond to a single Scud. Agreed that was the first generation Patriot not really optimized against missiles, but you get the point. The latest,PAC-3 is much better and if I remember somebody from DRDO (Chander, Saraswat), saying that PAD is similar to the Patriot....presumably he meant PAC-3.