My point is, the whole fucking world is complicit.

Most of the world is to an extent, but not all the world is war crime levels of complicit. Arming people with the knowledge they'll be committing war crimes is a war crime, full stop. Israel was bombing hospitals and aid workers from day one.

Should we be using this to drive yet another wedge among the left?

First, Harris is not part of "the left." Second, opposing genocide is basic human decency. For any vaguely left-lesning cause, someone who can't even do that much is less than worthless; they're a liability.