> the agreement not to expand NATO towards the east
This is a myth. There was a discussion in the midst of a negotiation that mentioned this. The final agreement, the Budapest Memorandum, which everyone is presently violating, did not.
There were multiple assurances made throughout the years in diplomatic comminques that were later declassified including James Baker's famous "not one inch eastward".
Lots of ideas were mooted and abandoned in the transcript [1]; it's revisionist to fixate on that one.
If you and I are negotiating the purchase and sale of a car, I say 10, you acknowledge my 10 and say 20, and we settle on 15, my heirs can’t later claim you said 10 and so agreed to it. That is the nonsense argument being raised here.
Even Gorbachev, to whom these statements were made, concurs he never understood there to be an agreement.
This is a myth. There was a discussion in the midst of a negotiation that mentioned this. The final agreement, the Budapest Memorandum, which everyone is presently violating, did not.