Sentence:  If the Union <WSD>conceded</WSD> this to them , the same right must be conceded to each remaining state whenever it saw fit to secede : This would destroy the federal balance between it and the states , and in the end sacrifice to the sovereignty of the states all the liberty the citizens had gained by their Union . 
Meaning of the word marked with <WSD> tags:  give over; surrender or relinquish to the physical control of another