Iskanders are surface to surface, and are supposed not to allow the ABM missiles to take off the ground and/or deny them radar guidance, increasing chances for retaliatory stike using land based ICBMs.
If they're just sitting on fixed platforms in the open - that's a little silly and pointless, isn't it?
At least if I was developing it I'd put in that capability and build the munitions. The Russians are shrewd weapons makers and I assume they would do the same.
I'd also give it a Surface-to-Air capability -- but that's just me. :-) A doo run-run-run, a doo run-run
