because it was between the Britain and American
The Stamp Act served as the "last straw" the colonists were willing to put up with from Great Britain and how it controlled the colonies. The Stamp Act was one of the so-called "Intolerable Acts" that Great Britain passed that harshly affected the colonies. The Stamp Act required every document and paper to bear a stamp, like postage stamps, which the colonists had to buy. All of the Intolerable Acts were eventually repealed except for the Stamp Act. Colonists recognized that this was just another way of Great Britain imposing more taxes on them and they objected to it. Great Britain refused to repeal it despite demands by colonists that it be repealed. This was part of the "no taxation without representation" sentiment at the time. King George 3rd insisted on enforcing the Act but this insistence only made the colonists more and more angry with him to the point where the majority of colonists finally had enough and decided to rebel and cut all ties with Great Britain. And so they did.and by the way America won the revolution!!!!!
This answer is completely accurate and true, but to answer your question in Laymen's Terms:
The Stamp Act only helped to further the reason for America to rebel against Great Britain's tyrannical rule over the Colonies. In this, it gave further evidence to the Colonial Rebels to secede from Great Britain for what oppresions they were having to deal with.