Russia to leave International Space Station by 2020

 It seems that Russia is taking the battle in Ukraine and Crimea into space. This seems like a move from Putin instead of the science community who I would think doesn't want this to happen. Scenes Russia has the only space ship that is usable and they take all of the other contributes to the Space Station, so if they leave how will all of the others get to the Station? Well if they leave then we will just build one or more with the other countries. A question that I have is, why does Russia have the space craft to start with?
    I hope that Russia comes to its scenes and does not leave but if it happens then we will find a new way to get into space.