"They too have been deaf to the voice of justice and consanguinity.”
Jefferson’s approach to these many appeals to British brethren is logical. He outlines each step the colonists have taken, and then ends with how the British citizens have turned their backs on the colonists.
This passage highlights that the colonists have not only been abandoned by their king, but by their fellow English citizens. The passage shows the colonists’ sense of abandonment, and then their resolve: either you are with us, or against us.