I guess you could always fall back on simple arguments. The...

I guess you could always fall back on simple arguments. The external powers who tried to benefit from the conflict have kept it going way longer than it would have without their 'support'. IMO

It is very much in European-NATO interests to support Ukraine. Ukrainians being used to fight mean that the other NATO Europeans don't have to. USA also has these interests.
I think we can all agree that, for these countries, supporting Ukraine is a very cheap [cost-effective?] way to make Russia suffer.

Or if you prefer a NATO mouthpiece:
[...] it is very much in our interest to support Ukraine, because they are fighting this war - we are not fighting it. So, I think we have to engage also in the dialogue with our American colleagues and friends, because they have the same interests. In a way, of course, supporting Ukraine is a very cheap way to make sure that Russia, this regime, is not a threat to the NATO alliance.
Dutch Defense Minister, Kaisa Ollongren.