Final answer:
The initial absence of an executive in the American government was due to a fear of tyranny and the desire for a decentralized power structure. This was reflected in the weak central government under the Articles of Confederation and the separation of powers. The eventual realization of the need for a stronger executive led to the formation of the presidency with checks and balances.
Step-by-step explanation:
The question of why there was initially no executive in the American government after the Revolution largely stems from a fear of tyranny. The leaders involved in setting up the new government were intimately aware of the dangers of giving one individual or a small group too much power, a lesson they learned from their experiences under British rule. They wanted to avoid creating any possibility of an elected or appointed governor or executive becoming too powerful, which in their eyes could lead to oppression and tyranny similar to what they had faced.
To combat this, they established a weak central government under the Articles of Confederation, initially relying on a loose alliance of states. Separation of powers was also paramount, to keep the three branches of government - legislative, judicial, and executive - independent and prevent any one branch from exerting undue influence over the others. Pennsylvania even went as far as not having a chief executive, opting instead for an elected governing council.
Despite these precautions, the inefficiencies of a weak central government, as demonstrated by Shays' Rebellion, soon made it clear that some form of stronger executive was necessary. This led to a careful rethinking about the role and powers of an executive, a process which culminated in the creation of the presidency with checks and balances in the United States Constitution.