As we move through the world assailing the various terrorists, we are going to allow our allies to protest where it is in their best interest to do so. That does not mean they will oppose us or that they do not support us. This is likely to happen with Russia, Pakistan, Egypt, Saudi Arabia, Jordan, Malaysia, etc. It is in our best interest that the rulers of those countries say whatever needs to be said to quell opposition from within.
Putin has to walk a bit of a tightrope to silence the dwindling old-line commies in his country. Note that his "opposition" to the ABM/NMD thing quickly morphed into quiet acceptance. When all is said and done, Russia and the US will end up jointly developing and deploying the system, because both countries need it. When my neighbor and me are both at risk of burglars and home invaders, the last thing that concerns us is maintaining a ten-foot high fence between our two homes.
Putin is faced with realpolitik considerations that require him to "demand" that the US include them in the plan, so that he can show that he negotiated it out of us as a concession. Unfortunately, he can't come out and say the obvious -- that the ABM treaty is meaningless, and that Russia needs NMD as much as the US does. So, he and Bush (and their close circles of advisors) worked out the plan, and now Putin plays for his constituency.