Im aware abt the south korean troop buildup, border clashes, that the peninsula being split in the first place was due to US meddling and the fascism, mass murders and rebellions in the south but im struggling to tie it together in a way that 1) fully makes sense 2) that id be able to explain to a normie without sounding like 
Also, if u have specific articles/sources abt the border clashes and general escalation from the south, id rly appreciate that 
From this post with many sources on a variety of topics about Korea
An extract from Churchill and the Bomb by Ernie Trory - I’ve read this and IMO it’s good - covers how the US sought to leverage an attack on Korea to escalate into war.
The US Imperialists Started the Korean War This is a 259 page book PDF. About 6 MB. I haven’t read it.