If there was a fire and you could only save 1 document that you felt was the essential American document would you save the Declaration of Independence or The Constitution? and Why?

I'm afraid there's no objective historical answer to this question. One could say the Declaration of Independence influenced revolutionaries from France to Vietnam, but one could also point to how the American Revolution prospered so much more than those others and attribute the difference to the Constitution. Or, one could attribute the difference to other factors and say the Constitution actually betrayed the principles of the Declaration. (Historian Woody Holton leans toward this view in his Unruly Americans and the Origins of the Constitution.) Or, one could judge what makes "the essential American document" on totally different grounds altogether.

So, any answer I could give would be merely my personal beliefs - and even then, I'm not completely sure. All I can say is that the Founding Fathers themselves disagreed. Jefferson felt the Declaration was more important; Adams felt the Constitution was; others, I'm sure, considered them both essential.