Israel has controlled the USG for decades now. We support Israel because they have been intricately and impressively spying on us since at least the 1980s and bought and paid for most of our politicians. It's just that simple, they own our politicians, and therefore: when they do heinous evil, our politicians look away.
Ukraine was invaded by our largest rival on the world stage as a power grab, and NATO decided to help.
The two situations are not comparable in the slightest.