The English had a long history of colonial policy making in relation to Ireland. Years and years of bloodshed and dissent had made the English so sensitive to popular protest that when the American colonies began their own protest movement it was met with what may have been overly harsh measures by the British government.
For generations Ireland had been harshly managed by the British government as a sub-standard colony. Violence, imprisonment and several quashed rebellions had resulted in a tense relationship between the two islands, but English colonial policy had undergone a transformation. There was little tolerence for disruptive or disobdient behavoir. British policies and acts of law were expected to be obeyed, regardless of what may or may not be fair in the eyes of British subjects.
After the French and Indian War when the British began taxing the American colonists there was much anger in parliment over what was, for the most part, a non-vilolent protest movement by the colonists. What the British saw instead was a total lack of respect for the authority of the British crown. They passed the Declaritory Act fairly soon after, stating the total control of the British government in making policy decisions for the colonies. This was not well recieved by the colonists in America because the same law had been used to crush a similar protest movement in Ireland several years before, and suddenly whispers of "tyranny" became louder and louder.
The Americans also worried about miltary force when the Coersive Acts were passed and Boston harbor was shut down. When similar acts in Ireland had occured, mass jailings and bloodshed was close behind. As a result, the American colonists began arming themselves for self-defense, and act that eventually led to the battles of Lexington and Concord and the outbreak of war.