Which economy policy was based on the idea that the american colonies existed primarily to provide economic benefits for great britain

The economy policy in which Great Britain based his pretensions over the American Colonies was the mercantilism.

 This theory is based in augmenting state power (British Crown)  at expenses of a rival nation goods (American Colonies). It aimed to accumulate monetary reserves by a positive balance of trade such as gold and finished goods. The way they made it possible was by conquering the most colonies they could and impose strong market regulations for the colonies to only trade with Britain. This policy, specially in the American Colonies was the trigger that start the American Revolution.

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Mercantilism

the answer is they believed george iii would never give them their freedom.