what concept did American colonists believed Justified their demand for a new government

The concept that American colonists believed justified their demand for a new government was that of "no taxation without representation." They argued that they should have a say in the laws and policies that affected them, especially when it came to taxation, as they believed they should not be taxed by a government in which they had no representation. This belief was a key factor in the eventual push for independence from British rule and the establishment of a new government based on democratic principles.