RAND 2019

In einem RAND-Strategiepapier von 2019 steht dazu:
"Overextending and Unbalancing Russia
Assessing the Impact of Cost-Imposing Options
....
Providing lethal aid to Ukraine would exploit Russia’s greatest point of external vulnerability. But any increase in U.S. military arms and advice to Ukraine would need to be carefully calibrated to increase the costs to Russia of sustaining its existing commitment without provoking a much wider conflict in which Russia, by reason of proximity, would have significant advantages."
https://www.heise.de/forum/p-37932042/