On the one hand, Biden needs to provide enough aid to Ukraine to, at a minimum, throw the Russians back to where they started, because if he doesn’t, Putin will just be motivated to try again in a year or two. On the other hand, if the Ukrainians are too successful, Putin may escalate to the point that a nuclear war is all too thinkable.
It’s a tightrope act. In the real world, which is messier than any theoretical version, it is unlikely we will be totally successful. That’s just the way it is.
Just be grateful Biden is president right now. Can you imagine what would be happening if Trump were in office today?