What do you think would happen theoretically if such a document would be released?
This is from a short story from Matthew Reilly, I didn't pull this idea out my head. (Annoyingly, I had to type it, I couldn't copy it from the .pdf file

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Dear Herr Hitler,
It is with grave feelings that I write to you today.
Despite our differences, our two great nations are in many ways, similar. Ours are proud nations, strong nations.
In times such as these, my country, like yours, has concerns about the future - about current alliances, and of course, the Soviet issue.
And although, in the past the United States has preferred to remain isolated from conflicts such as the present one, there comes a time when a country must make a decision that will ensure its future, and as such choose allies based not on past allegiances, but on what is best for the nation in the cold hard light of reality.
Although our two nations have traded indirect blows in this burgeoning conflict, the United States is not yet a formal part of this war. Our entry into it, however, need not occur at all.
In this vein, Herr Fuhrer, I propose an alliance between our two great nations - between Germany and the United States of America - that will supercede any previous treaties my country may be party to.
I await your reply. In the mean time, I remain,
Yours sincerely,
Franklin Delano Roosevelt
President of the United States of America
Also, I think
that if I was the current president of America and someone threatened to release this document if I didn't do X, I would stay 'Go ahead and release it for all I care, this was in the past and is irrelevant now.' I mean, most people don't care about Italy being allied with WWII Germany.
If someone finds this thread offensive, sorry, I just want to see what other people think of this. 