Yeah, yeah, yeah, shouda, coulda, wouda. PROOF man!
Things that were “self evident” as you put it came from English common law, not Vattel. Vattel’s book was originally published in 1758. How many colonists knew his work to make it “common” knowledge? Are you for real?
Are you seriously posing that Vattel was “self evident” during the revolution? That’s 18 years for pete’s sake yet all colonists took this guy’s theories to heart. THIS IS INSANITY!!!!!!!
As for the other dicta you cite; that and $5 will get you a cup of coffee at Starbucks.
Regarding Franklin, in 1775 he wrote to Charles Dumas, an editor and journalist in the Netherlands, and thanked him for sending Franklin 3 copies of the newest edition of Vattel (published in French). Franklin commented to Dumas that his personal copy was in heavy demand by the other delegates to the Continental Congress meeting in 1775.
To quote: "I am much obliged by the kind present you have made us of your edition of Vattel. It came to us in good season, when the circumstances of a rising state make it necessary frequently to consult the law of nations. Accordingly that copy, which I kept, (after depositing one in our own public library here, and sending the other to the College of Massachusetts Bay, as you directed,) has been continually in the hands of the members of our Congress, now sitting, who are much pleased with your notes and preface, and have entertained a high and just esteem for their author."
If they were consulting it in 1775, don't you think they might have thought about it in 1787?
Also, Washington himself set a world record for overdue library books, by checking out a copy of Vattel from the NY Public Library, which was not returned for 220 years! He must have thought it worth keeping for reference.