80% you say on the SM-3, well that is even worse than what I said with 90%. It means that statistically when you try to stop 5 incoming missiles, one of them will get through.
The budgeting thing also is not correctly given by you, becasue you have to compare the 21D not to a cruise missle, but to a carrier and its fighterwings, and I would argue also to the attached flotilla protecting the carrier, because certain ship classes like the Aegis cruiser exist only because of just one single job of theirs: to protect carriers. That'S what they were designed for.
Carriers are top priority targets for the Chinese. The 21D is a cheaper solution to neutralise them, even if they are needed by the dozens to defeat the carrier's defence by "flooding" them. And as it is claimed: you need only
one 21D hitting the target in order to
obliterate it. Do you really want to bet your money on the carrier when let'S say 16 21D are fired, that they all will be shot down, all 16? You can assume that they will be equipped with the latest navigation systems by the Chinese. Already today their flight path characteristics are described to be "tricky" to be tracked.
I think you are uncritically too convinced by US technology here. But China really is no longer fighting with stones and axes.
You better start to take them serious, before your sailors will need to learn the lesson the hard way. I think the Pentagon has started to understand this. The Chinese submarine threat, the cyber threat and the missile threat are now priority concerns, it seems to me.
Let'S do like any good pilot: let'S not assume that the autopilot should be trusted blindly.