A quote from James Madison

The advice nearest to my heart and deepest in my convictions is, that the Union of the States be cherished and perpetuated. Let the open enemy of it be regarded as a Pandora with her box opened, and the disguised one as the serpent creeping with his deadly wiles into paradise.

— From 'Advice to My Country' written shortly before his death. He had it sealed and opened only after he passed away. [1836]