What are the factors that led to the Separation of Singapore from Malaysia? .
I define "leading to Separation" as the the explicit disagreements and conflict stemming from tacit agreements that indirectly or directly played a part in the final decision of Separation.
Political .
The clash of ideologies brought about the inability to maintain the agreement. The main difference in PAP and the Central Government's ideals was that PAP favored the idea of meritocracy while the CG acted according to a communal approach in politics. Yet another clash of ideologies was that while Singapore viewed itself and Malaya as equals in Malaysia, Malaya thought merger was where the weaker party (Singapore) sought the protection of the stronger (Malaya). As such, the CG expected the PAP to adopt to the system already in place which was something PAP had no intention to do right from the start. This ideology was expressed in PAP's campaign for a "Malaysian Malaysia" in the 1964 Federal Elections as a retaliation to the Singapore Alliance's futile attempt to contest in the Singapore Legislative Assembly in an attempt to appeal to the Malays in Singapore. Essentially, while Malaya thought it was entitled to try to influence the Malays in Singapore and compete in Singapore's Legislative Assembly, Malaya also thought that Singapore was not justified in running in their Federal Elections. Whereas Singapore saw the merger as an equal partnership and hence did not pardon the fact that the Singapore Alliance was running in their election. The Alliance Leaders saw this campaign for equal treatment regardless of race as a slap in the face and a direct challenge to the Alliance's supremacy in Malaysia, as if to criticize the way Malaysia was governed by the Alliance. This sparked off a series of mutual attacks such as the Anti-PAP campaign started through the Utusan Melayu, and the Anti-PAP speeches at Prophet Muhammad's Birthday at Geylang.