Question:
What would Ukraine have done had the US not honored its agreement with them just as Ukraine did not honor its agreement with Russia?
I think the honest answer, acted upon, would have proven to have prevented bloodshed and what little destruction there has been.
Instead of the US mediating through diplomacy, they gave a gun and encouragement to their "little brother" to fight back against the "school bully", so to speak.
Casting the Ukrainian people into eternal indebtedness by goading them into an unwinnable war benefits whom?