The Right to Self Determination

 When, in the course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the laws of nature and of nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.

Prudence, indeed, will dictate that governments long established should not be changed for light and transient causes; and accordingly all experience hath shown that mankind are more disposed to suffer, while evils are sufferable, than to right themselves by abolishing the forms to which they are accustomed. But when a long train of abuses and usurpations, pursuing invariably the same object evinces a design to reduce them under absolute despotism, it is their right, it is their duty, to throw off such government, and to provide new guards for their future security.

from the Declaration of Independence

It was in this document that the right to self determination was first assumed. It is by no accident that the rights is enshrined in modern United Nations Convenants as the Declaration of Human Rights was a joint production between the United States and the United Kingdom. Since the United States only came to be through the exercise of this right there can be little doubt that it would be included.