http://www.civilwar.org/.../declarationofcauses.html
The Declaration of Causes of Seceding States
Primary Sources
Texas:
Texas abandoned her separate national existence and consented to become one of the Confederated Union to promote her welfare, insure domestic tranquility and secure more substantially the blessings of peace and liberty to her people. She was received into the confederacy with her own constitution, under the guarantee of the federal constitution and the compact of annexation, that she should enjoy these blessings. She was received as a commonwealth holding, maintaining and protecting the institution known as negro slavery-- the servitude of the African to the white race within her limits-- a relation that had existed from the first settlement of her wilderness by the white race, and which her people intended should exist in all future time. Her institutions and geographical position established the strongest ties between her and other slave-holding States of the confederacy. Those ties have been strengthened by association. But what has been the course of the government of the United States, and of the people and authorities of the non-slave-holding States, since our connection with them?
When we advert to the course of individual non-slave-holding States, and that a majority of their citizens, our grievances assume far greater magnitude.
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The States of Maine, Vermont, New Hampshire, Connecticut, Rhode Island, Massachusetts, New York, Pennsylvania, Ohio, Wisconsin, Michigan and Iowa, by solemn legislative enactments, have deliberately, directly or indirectly violated the 3rd clause of the 2nd section of the 4th article [the fugitive slave clause] of the federal constitution, and laws passed in pursuance thereof; thereby annulling a material provision of the compact, designed by its framers to perpetuate the amity between the members of the confederacy and to secure the rights of the slave-holding States in their domestic institutions-- a provision founded in justice and wisdom, and without the enforcement of which the compact fails to accomplish the object of its creation. Some of those States have imposed high fines and degrading penalties upon any of their citizens or officers who may carry out in good faith that provision of the compact, or the federal laws enacted in accordance therewith.....
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...based upon an unnatural feeling of hostility to these Southern States and their beneficent and patriarchal system of African slavery, proclaiming the debasing doctrine of equality of all men, irrespective of race or color-- a doctrine at war with nature, in opposition to the experience of mankind, and in violation of the plainest revelations of Divine Law. They demand the abolition of negro slavery throughout the confederacy, the recognition of political equality between the white and negro races, and avow their determination to press on their crusade against us, so long as a negro slave remains in these States.
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They have proclaimed, and at the ballot box sustained, the revolutionary doctrine that there is a 'higher law' than the constitution and laws of our Federal Union, and virtually that they will disregard their oaths and trample upon our rights.
They have for years past encouraged and sustained lawless organizations to steal our slaves and prevent their recapture, and have repeatedly murdered Southern citizens while lawfully seeking their rendition.
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We hold as undeniable truths that the governments of the various States, and of the confederacy itself, were established exclusively by the white race, for themselves and their posterity; that the African race had no agency in their establishment; that they were rightfully held and regarded as an inferior and dependent race, and in that condition only could their existence in this country be rendered beneficial or tolerable.
That in this free government *all white men are and of right ought to be entitled to equal civil and political rights* [emphasis in the original]; that the servitude of the African race, as existing in these States, is mutually beneficial to both bond and free, and is abundantly authorized and justified by the experience of mankind, and the revealed will of the Almighty Creator, as recognized by all Christian nations; while the destruction of the existing relations between the two races, as advocated by our sectional enemies, would bring inevitable calamities upon both and desolation upon the fifteen slave-holding states.