As to Ukraine I think a few things were going on

We really feared Putin escalating early on. We also feared Ukraine folding in the first month.

As to Tanks, we assessed that Abrams were not the tanks you wanted to start them off with. We ended up releasing our tanks to shame the Europeans into giving up the Leopards Ukraine wanted.

With the financial shortage (imposed by MAGA) we didn't want to focus on big ticket items in later packages to eat up the financial runway we have left.

I think the war likely goes into 2025 whatever happens with negotiations or an armistice. The terms will be decided by balance of power.

It's in our selfish interest to see Russia attitudes as much as possible. We don't want Putin to be able to sell this as a win and keep expanding into countries with Russian minorities like the Baltics. It's also in our interest to integrate Ukraine into the EU/NATO infrastructure to further deter Russia/reduce the need for American boots on the ground in Europe.

We need to fund them so they can hold the line this year and shame Europe into contributing what they really need to be doing. Our generals and theirs are painting a pretty dire picture of what happens when their ammunition/air defense shortage gets worse than it already is.