With Anti Missile Defense I think we have problem with National Psychology.

On one hand we have Russian who fear of being defenseless - Nazy invasion was such a disaster which almost destroy Russia as a country or as Nation. 30 million people died mostly defenseless civilians who were butchered by Arian Higher Beings - Nazy who think that they are better and so kill Russian civilians by millions, shoot them, burn them alive, starve to death... For Russian invasion like this is bit different then for let say Frenches who were not wasted by Germans same as Russians (Germans did not fear French and so did not hide their fear under brutality). This loses are not very well known on the West, but every Russian know about this not only from history books, but from every family history because every single Russian was affected and have relatives lost. Every men born in 1923 never - who was 18 at 1941 died in that War. So for most Russians it is psychologically impossible to feel not to be ready to prevent invasion. This is why US building anti missile shield is simple not acceptable. Russia will go back to poverty, if needed, but will never allow anyone in the World to be able to attack Russia, to do what Germans did at 1941-1945.

On other hand we have Americans who get used to think about them self as best in the World by any means, until Sputnik was launched. This scare shit out of entire America! It was clear, impossible to hide demonstration that this is not a case. It starts mass hysteria mass nuke fear. It was made even worse during Cuban crisis, when Florida residents run away from Russian nukes. All that create huge psychological complex, irrational fear of Russian missile attack. This fear mobilize United States, make it focus on science, math, physics, pump billions of dollars in 1950th in education which eventually turns into modern technologically advanced US (it seems that now there is no motivation for this and science and math in US not very strong any more, which most likely affect following generation in a bad way). But missile defense is ultimate answer on this over fifty years old Sputnik fear. It looks like this is as well impossible for Americans to give up.

Most probable development I see - new arms race. Keep in mind that this time it will not be half dead members of Politburo - it will be Putin team which already prove to be quite effective. You may like him or not, but results of his work is hard to ignore. From ruin of USSR his team create modern healthy country. Russia has all kind of resources - from natural to brain power. This will be pretty tough enemy to fight. And most interesting is that Russian do not really want to fight, they will be happy to be friends, not servant of course but friends. It is really hard to blame Russian in any wrong doing, in something they do against US. They squeeze Brits from European energy market, but this is Brits problem not US. Russian did not blindly support what happen in Libya and in Syria - but it is more Qatar problem which taking over one Arab country after another.

I do not really see what Russia do to make US not to be friend. Or I do not really see anything which may justify making Russia enemy and start new Cold War and Arms Race. Why? Just because Brits do not want to see Russia's oil and gas in Europe? Because Russia do not make it easy for Qatar to take over Syria? I doubt that US really care much or should care about those guys. It is all about National Psychology and it is really hard to change entire nation set of mind... So US is going to build Anti Missile Defense out of old Sputnik fear and Russian will build a thousands and thousands of missiles to penetrate it or came up with some other weapon to make things even.

This will push US and Russia away from each other much more. Both country will start to hurt each other in any field in any place. US enemies everywhere will start getting modern Russian arms, now they have outdated sniper rifles and armor piercing grenade launcher from old Soviet satellite countries stocks, but it will be all new... It will be good old Cold War back and it will not be based on illusional Communist Economy, but on modern one which Russia already build. and it function quite well - it toke Global Crisis hit better then many other developed counties and it does not face new Crisis.

I do not really see how US or Russia will benefit from this...

However, I do not really see how this is not going to happen...