Answer:
The British expected to improve their defenses against native attacks, increase the control over trading and taxes, as well as reinforce their power in the colonies by creating a well organized mechanism by establishing the dominion of New England.
Explanation:
First of all the Dominion was a strategy to improve New England's defenses against native attacks. King James II figured out that by advancing into the American soil and continue to develop the colonies. They were going to get attacked in a bigger way, which lead him to organize a system in which New England could be straightened to keep expanding with security forces to grant them the safety required.
In the second place, trade and taxes weren't controlled before the Dominion, but after they realized the tax and trade systems weak they decided to improve it by tightening it. They first improved the Navigation Acts by limiting the goods colonists could produce, then they established that New England colonist was only able to sell their goods to England or other England Colonies. It was the result of the New England colonists' trade relations with the Spanish and Dutch businessman. But it lead to smuggling activities and black market creation, which eventually produced that all these trades who didn't follow the rules were put out into justice.
In third place the establishment of an effective bureaucratic system. Before the Dominion England wasn't able to maintain control over the colonies, because they were all governed individually. However, the idea of establishing a dominion would bring a serious ruler to keep all the governors at pace and make them follow the King's mandates.
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