> That is extremely unlikely to happen.

That's what very much has already happened. Visa and MasterCard pulled their services a few years ago after another set of US sanctions. Also, if you are a business and using SWIFT to transact - US has the final say what you can and can not do. So now Russia has it's own payment card system MiR and working with China, India and even Iran on alternative to SWIFT.

I think it was a mistake for US to retract payment services. A smaller country may be severely affected by it indeed, but not a country of the size of Russia, China or India.

Now if payment networks were pulled, then what is next? Internet would be the logical follow-up. Hence the testing. It all makes perfect sense when you look at it from Rissia's side.