Final answer:
Brutus's concern was that a strong central government with a large army would take away people's rights.
Step-by-step explanation:
Brutus's concern about the power of the federal government to raise large armies was that it would be easy for the government to take away people's rights. He believed that a strong central government with a large army would encroach upon the liberties of the people and potentially lead to tyranny. Brutus worried that the government could use the army to suppress dissent and control the population, eroding the individual rights of citizens.
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