Everyone looking at the price tag vs the results knows a proxy war with a well-trained army, the side of the US and Ukraine, against formerly your biggest adversary is the least costly way to cripple your foe while hardly lifting a finger.
~$125 billion TOTAL, including humanitarian, in a sea of $800B+/yr is play money in war, and throwing Russia back with dollars is the largest blow to a man who thinks he’s militarily strong.
It even makes China hesitate. I’d pay a lot more just for that.