That's a funny way to phrase it, but ostensibly, yes Palestine is the side which has a right to exist and is not a settler colonialist entity.

The reason behind the post is the irony behind a CIA official recognizing this, when the CIA has undermined Palestinian freedom (and the freedom of countless other nations and groups).

“Heartbreaking” is an inside joke in reference to “Heartbreaking: The Worst Person You Know Just Made A Great Point.”

Yes, in the most reductive but broadly true terms possible: CIA (or US and Israel) is the "bad side" and Palestinians are on the "good side."

The US and Israel, which the CIA and Mossad are the weapons of, represent oppression, land theft, murder, genocide.

Palestinians are oppressed by the US/Israel. Their individual actions may not always be described as "morally good" but in the grand narrative their cause is always righteous and just.

People on the side of injustice and unrighteousness would rather have you focus on single individual actions that most people can agree, in isolation, are morally bad. They want you to forget all context that led to that action, they want you to condemn the righteous cause based on those isolated events, they want you to side with the unjust.

That's how I would better frame it, btw. If you want a reductive, quick framing you have a side that fights for justice and one which de facto is fighting for injustice.

Much like slave revolts throughout history including in the US. Just as anti-apartheid resistance in South Africa was sometimes violent. Just as every socialist and communist revolution has to have an element of violence. Those who oppress others will never relinquish control without force and condemning the enslaved or oppressed for how they fight their brutal enslavers is never the correct outlook.

(Got ADHD sidetracked, oh well)