The stance toward foreign policy that suggests that the United States should "go it alone," pursuing its national interests without seeking the cooperation of other nations or multilateral institutions is known as: Nativism. unilateralism. isolationism. multilateralism.

unilateralism

Explanation:

Unilateralism mode of government is a style of government that favors taking a decision or policy concerning its foreign affairs alone without consulting other foreign nations or allies.

In other words, it involves a situation in which a country doesn't involve an International institution in its foreign activities or affairs. It is the opposite of Multilateralism.

Hence, in this case, the correct answer is UNILATERALISM.

b: the establishment clause  

b: socialism