[varren]

1) yes, the race is still on. I don't want to go deep into the politics and talk about who triggered what, but the breakpoint was the USA withdrawal from Anti-Ballistic Missile Treaty(1972-2001)[1] and development of Aegis Ballistic Missile Defense System(2002)[2] and Terminal High Altitude Area Defense(2008)[3] and some other projects in that field. It can look like not a big deal, but it is actually a crucial step to escalation, because if you don't feel safe enough (without anti-missile system good enough to protect you) you will never strike first. But if you have such a system what stops you from using nuclear weapons? At least that was the main idea behind the first ABM Treaty (1972). Back in the days USSR had huge progress in that field, and now USA can easily create superior systems in a couple of years. While China and Russia don't have the same resources, the only thing they can do is to improve nuclear weapons(because it is cheaper). And after all SALT I (1969–1972), the ABM Treaty (1972), SALT II (1972–1979) are all part of the same deal. So yes, we can say that the world is changing and old system of mutual nuclear disarmament is not working anymore. And it can't actually work in the world where new nuclear power emerge every 10 years or so...

2) don't think so. Some leader bragging about some 'invincible' weapon before the elections is not a big deal.

[1] https://en.wikipedia.org/wiki/Anti-Ballistic_Missile_Treaty

[2] https://en.wikipedia.org/wiki/Aegis_Ballistic_Missile_Defens...

[3] https://en.wikipedia.org/wiki/Terminal_High_Altitude_Area_De...

[AnimalMuppet]

The US had to do something like this because of North Korea. We trust deterrence with Russia much more than we do with North Korea.

I don't thing ABM defenses really change things. Russia can throw 2000 warheads at us. Can we stop them all? No way. But would we have a chance at stopping one North Korean nuke? Yes.

So I think this is only destablilizing if Russia and China decide that it is. If Russia is looking realistically at the situation, there is exactly zero chance that the US will willingly take the amount of damage that Russia could cause, even with ABM defenses reducing the damage.

[varren]

ABM defenses change things in a context of mutual nuclear _disarmament_ not in ability to annihilate each other. If USA stops playing according to the agreements, why others should?

Yes, USA is saying that it has to come up with something like this to counter rogue states and I can believe that. But why should Russia/China or any other country keep their part of the mutual nuclear disarmament bargain in that case? (ABM defenses is part of the deal here) Everyone has a different view on how to enforce peace. There is actually a theory in international relations that the safest earth can get is when everyone have nuclear weapons capable of destroying everyone else.[2] And it is part of a neorealist theory so Russia and China are pretty "realistic" in their approach. To be honest the safest way for any country is to have such a weapon that can crush the earth if used. Is it safe for humanity? No. But it is definitely the safest way to ensure your regime.

"The US had to do something like this because of North Korea" Well, USA never did anything about Israel, Pakistan, India. There are 10+ more countries "being one screwdriver's turn" from the bomb. Why bother now? And here is another POV: Initially ABM defense was advertised to stop Iran ballistic missile development and USA sold lots of Aegis parts to Europe/Turkey/Saudi Arabia. And Russians freaked out about radars in Poland covering most part of western Russia and backed Iran... And I think they had their reasons for concern because Poland wasn't even in range of Iranian missiles at that time. And it goes on and on, but anyway it pretty much started the new race on a global scale. Doesn't matter who was the first: India/Pakistan/NK/Iran, ABM escalated it to a completely new level. Btw i doubt many ppl know that it was Pakistan who started NK nuclear development in 2002.[2]

"But would we have a chance at stopping one North Korean nuke? Yes" And that's the real danger. If someone in Japan or South Korea think the same, that they are truly protected with this shield, they will have strong desire to influence/provoke North Korea/ try a regime change... And that can cause a full scale war with nuclear state. The point here: is it really secure or just an illusion of security? And btw North Korea probably has more that just 1-10 or even 100 nukes at this point.

[1] https://en.wikipedia.org/wiki/Nuclear_peace

[2] https://en.wikipedia.org/wiki/North_Korea%E2%80%93Pakistan_r...

[AnimalMuppet]

> Well, USA never did anything about Israel, Pakistan, India.

Under current circumstances, neither Israel nor India are going to even try to attack the US. Pakistan might be tempted, but I believe they don't have a ballistic missile capable of reaching the US. So there was less reason to do anything about them. (Iran, now, is more worrying.)

> If someone in Japan or South Korea think the same, that they are truly protected with this shield...

But I don't think anybody believes that. Could it stop a North Korean nuke? Hopefully, yes. Is anyone confident enough to want to try it? I doubt it; nobody believes that ABM defenses are anything like 100% reliable.

> And btw North Korea probably has more that just 1-10 or even 100 nukes at this point.

I think it's about 10-20 warheads. Do they have 10-20 ICBMs that are operational? I doubt it, but I don't know for certain.

[varren]

Well, you may be right, it is just a matter of interpretation. But when it comes to defence in international relations it is basically a variation of Prisoner's dilemma[1]. It doesn't matter what reasons USA has to develop ABM. Russia, China, NK and everyone else will never choose to disarm when their oponent is arming.

[1] https://en.wikipedia.org/wiki/Prisoner%27s_dilemma#In_intern...