hm...not sure about vietnam navy calculus. I guess many things are unknown to outsiders like you and me.
Russia has resources to withstand the attack right now. BUT should the West increase the economics sanction and the oil price further sinks to unsustainable level, so less than $50 a barrel, over a long period of time. All would make a perfect storm. Russia could default in 1-2 years as it won´t be able to pay back debts.
I doubt China would help Russia without conditions. the Chinese are too smart if they won´t seize the opportunities. Even the currency swap deal with China will cost Russia a lot of money if the russians are forced to draw it.
We concluded about 100 billion $ deal with Russia and China also concluded 400 billon$ deal with them.But I am afraid that is not going to help them.
On topic:The requirements will determine by VN not us.Only thing we can do is to propose our designs.
But I think the VN govt aims to draw us in to SCS game.
