The post Oct-7 anti-Hamas propaganda was the most intense, IMO. But Ukraine is a close second.
It was much more all encompassing, but despite that, millions of people even in the heart of empire saw through it, it wasn't very successful in making people in the west sympathise with genocidaires, even when most people in the west previously had sympathised with them. There have been a lot of pro-Palestine protests, despite the media and police response to them. But I haven't seen any "stop the war" protests in the west trying to put an end to the Ukraine war.
Nobody likes that! So they double down instead and become increasingly unhinged.
And I think this is why libs always end up trailing 3-5 years behind conservatives on unhinged nonsense, the conservatives have always been living in a "post truth" headspace, but libs are still in denial about it.