I don't see how this missile shield can protect the U.S or it's allies from the sheer number of Russian ICBMs. The "protection" offered against Russian ICBMs is so minimal as to be insignificant. Hence it holds no strategic influence at all. Secondly even if it did Russia claims not to be an adversaries so why the need for equilibrium
The Russians are just conveniently using it as pretext to justify their attempts to restore themselves to their former glory that so obsesses their dictator
Alan, it does not appear like you read my post or, if so, it seems like you didn't understand it.
I'll try explaining again: In an all-out nuclear exchange between two superpowers, you've got only two shots at the other guy - your initial salvo and your second strike after your opponent has replied in kind. The second strike will likely come from mobile forces, SLMBs, B52's etc. as the silo-based forces will likely have been destroyed after the first exchange. That's also why the silo-based forces will probably be used during either a first strike or as a response to the other guy's first strike.
The end result of these two nuclear exchanges will be the total annihilation of the command and control structures of both countries and their allies as well as a significant percentage of each country's military hardware - hence the term MAD. MAD is what keeps these guys from attacking each other in the first place.
Now, provided that you've got nuclear parity - as is currently the case between the USA and Russia - then nobody can win in a nuclear exchange; both will be obliterated. However, once the one side comes up with a way of diminishing the effectiveness of its opponent's first strike, you'll rapidly lose parity due to the fact that the other side will have to significantly increase their resources allocated to a first strike against targets protected by a missile shield.
This greatly diminishes the other side's ability to launch an effective second strike. In reality, you lose parity, giving the guy with the missile shield a decided advantage. This leaves the other guy with no other option but to increase the size of his arsenal. This leads to a new strategic arms race.