The union created when member countries of an economic and monetary union work closely with one another to arrive at common defense and foreign policies and behave as a single country is known as a(n

Political union

Explanation:

Political Union is a union created when member countries of an economic and monetary union work closely with one another to arrive at common defense and foreign policies and behave as a single country.

Political union is when smaller states come together to form one state.

Forms of a political union includes:

Incorporating union

Incorporating annexation

Federal (or confederal ) union

Federative annexation

Mixed unions

I hope my answer helps you.

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