Giving Ukraine all the weapons it needed and asked for, instead of destroying them soon, would be a good start. Also, you know, not forbidding Ukraine to use its long-range drones to damage Russia's oil industry would also be helpful. This is to get started. I can continue.

According to many economists we were already on a very good way to beating them (ruining them) with existing sanctions alone.

Winning the attrition war. They have most likely less than a year left before their economy crumbles. 21% interest rates, capital controls, official 10% inflation, annihilated non military sectors (fe cars), forcing their banks to give loans to anything military adjacent while forbidding them to call them in.......

I am sure the Europeans would be willing to shoulder more of the cost but the US has been cutting Ukraine off from intelligence sources and now also support. There is no cost argument for that.

Also do you really think that these decisions will not cost the US in lost sales, reassurances for everything because of lost trust....