I think part of the issue here, that we here in Europe don't fully appreciate is that the US is by far the biggest doner to Ukraine and for many Americans they simply have other priorities.
Most of us in Europe better understand the threat from Russia. Whether it's from seeing the war on our continent, greater impact on our food and fuel costs, to just having millions of people who lived under the oppression of Soviet communism, it's a threat that is far closer to home for Europeans, literally and figuratively.
Most Americans probably couldnt point to Ukraine on a map (and before we scoff, how many Europeans could point to Bolivia or Ecuador?).
We need to understand this thinking a bit more as I think it's driving a lot of the US governments thinking. Ie, "not our problem, but we are paying most for it".
Not saying that's the right way to think but I do think it's an issue and for many Americans I can see why they can think of better things to spend their money on.