Seriously, why is the USA supporting Israel?

The US is supporting Israel through what we can mostly all agree is a genocide of the Gazans. Clearly, Biden isn't a genocidal maniac, yet he's all in with unwavering support. Why are we doing this? There has to be a logical reason that isn't just "we want Israel to kill everyone in Gaza and take their land a la lebensraum."

We know this is an emotional topic, so please be respectful of each other so that we can have open and clear authentic discussion on the matter.