Congress passed the militia act in order to

a. draw military aid from overseas nations.
b. allow african americans to join the military.
c. expand union presence in western territories.
d. give border states the right to defend themselves.

in this case i think the answer would be c.

Explanation:

The Militia Acts of 1792 were a pair of statutes enacted by the second united states congress for the organization of the state militias and provided for the US president to take comand of the state militias in times of imment invasion or insurrection.

(b) britain had a much larger navy than the u.s.

(d) the u.s. had a small army compared to britain.