The taxation began in the 1760s, the Boston Massacre occurred in 1770, the Boston Tea Party in 1773, and the Battles of Lexington and Concord in April of 1775.
Patrick Henry's call to action, "Give me liberty, or give me death," was the first strong public statement that, if we were to be free, if we were to have liberty, then we would have to fight Britain. Prior to Henry's speech to the gathering of Virginia delegates in Richmond, the prevailing belief was that we could negotiate with Britain.
Henry lay down the gauntlet and clearly presented his understanding of what we were facing.
Our choice was liberty or death.
Our founders chose to take the challenge and declared our independence from Britain on July 4, 1776.
Our Declaration of Independence is a three-part document: the first a declaration of freedom, including our understanding of the natural order of authority and power; the second a long list of grievances, reinforcing the belief that there was no choice but to declare our independence as a free country; the third an acknowledgment of risk and the oath of the signers to one another.
The first section is the one that is most often quoted: "We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness. -- That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, -- That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness."
This introduction represents the core of American Exceptionalism. We are exceptional as a nation not because we are inherently better people (people are the same everywhere), but because our government is built on a different structure than those of other countries. Our founders understood and articulated our belief in a creator (God), who endows people with rights. The people then loan the rights to the government to secure their individual rights (life, liberty, pursuit of happiness).
The introduction also provides for recourse if government becomes destructive to individual rights, "to alter or to abolish it," meaning the government.