Final answer:
Concerns about the cost, potential opposition from Native American tribes, political disputes including the extension of slavery, and doubts about the constitutional authority to acquire territory were reasons against the Louisiana Purchase.
Step-by-step explanation:
Some historical reasons for not making the Louisiana Purchase include concerns about the cost and its impact on the federal budget, opposition from Native American tribes in the region, political disputes and concerns about expanding slavery, and fear of conflicts with European powers.
Constitutional concerns were significant, as President Thomas Jefferson grappled with whether he had the authority to acquire new territory, given that nothing in the Constitution explicitly granted such power.
The Louisiana Purchase, however, provided significant benefits such as control of the port of New Orleans, doubling the size of the United States, and bolstering westward expansion despite the challenges it posed, including deepening the division over slavery and provoking Native American resistance.