On the ABM's Putin has clearly explained his concerns relating to their proposed sighting. He knows and has acknowledged that they in themselves pose no direct threat to Russia, he knows exactly what threat they are being deployed to cover. His concern is that if fired from their intended locations at missiles fired in a "rogue" strike the ABM's might take out the IRBM's in locations that might cause their (the IRBM's) warheads to fall on Russian territory.

Point indicating the above to be the case - Putin himself actually advocated alternative sites for these ABM's and for their guidance radars, the locations being equally on "Russias Doorstep" but where if struck the targetted IRBM warheads would fall into the Caspian Sea.