It sounds like the US is offering the Russians a fig leaf to hide their inadequacies. By claiming the Russian missiles are still invulnerable, we can head off the political call for a new round of ICBM development by the Russians. The Russians don’t want to spend this kind of money, so they are happy to accept the falsehood.
It stands to reason that any interceptor fast enough to catch an Iranian missile would be fast enough to catch a Russian missile.
The Israelis were able to strike Syria a couple of weeks ago unscathed. Apparently, the big bucks Russian air defense system that Syria had recently purchased from the Russians didn't so much as give a hint that the Israelis were coming. With all the closet cleaning the Russians have been doing lately, selling arms and air defense to all comers, I'd tend to think the Russians need quite a few fig leaves to hide their inadequacies......
Needless to say, there is egg all over the faces of the lefty apologists for Bush's appeasement policy here...with the Russian Generals saying they are keeping their SS-18s until at least 2017 (when they are apparently needing to be retired due to unreliability)