as far as your source's wishful thinking about the danbury letter, on the library of congress' site, youll find a long discussion by a curator who had the fbi use cutting edge technology to help restore jefferson's notes and deletions on the original letter. using those and jeffersons other papers, he notes the following (i bolded the text for emphasis):
Airing the Republican position on church-state relations was not, however, Jefferson's principal reason for writing the Danbury Baptist letter. He was looking, he told Lincoln, for an opportunity for "saying why I do not proclaim fastings & thanksgivings, as my predecessors did" and latched onto the Danbury address as the best way to broadcast his views on the subject. Although using the Danbury address was "awkward" -- it did not mention fasts and thanksgivings -- Jefferson pressed it into service to counter what he saw as an emerging Federalist plan to exploit the thanksgiving day issue to smear him, once again, as an infidel.
Jefferson's hand was forced by the arrival in the United States in the last week of November 1801 of what the nation's newspapers called the "momentous news" of the conclusion between Britain and France of the Treaty of Amiens, which relieved the young American republic of the danger that had threatened it for years of being drawn into a devastating European war. Washington had proclaimed a national thanksgiving in 1796 to commemorate a much more ambiguous foreign policy achievement, the ratification of Jay's Treaty that attempted to adjust outstanding differences with Great Britain. Would Jefferson, the Federalists archly asked, not imitate the example of his illustrious predecessor and bid the nation to thank God for its delivery from danger by the Treaty of Amiens? The voice of New England Federalism, the Boston Columbian Centinel, cynically challenged Jefferson to act. "It is highly probable," said the Centinel on Nov. 28, 1801, "that on the receipt of the news of Peace in Europe, the President will issue a Proclamation recommending a General Thanksgiving. The measure, it is hoped, will not be denounced by the democrats as unconstitutional, as previous Proclamations have been."
The Centinel and its Federalist readers knew that Jefferson would never issue a Thanksgiving proclamation, for to him and the Republican faithful in the middle and southern states, presidential thanksgivings and fasts were anathema, an egregious example of the Federalists' political exploitation of religion. Federalist preachers had routinely used fast and thanksgiving days to revile Jefferson and his followers, going so far in 1799 as to suggest that a Philadelphia yellow fever epidemic was a divine punishment for Republican godlessness.*
During the Adams administration, Republicans organized street demonstrations against presidential fast days, ridiculed them in the newspapers and boycotted them. Since Federalists knew that Jefferson would never proclaim a national thanksgiving to praise God for the Treaty of Amiens, they calculated that they could use his dereliction as evidence of his continuing contempt for Christianity, which had spilled out again, in their view, in his invitation to "Citizen" Thomas Paine to return from France to the United States.
To offer the nation's hospitality to Paine, author of The Age of Reason, the "atheist's bible" to the faithful, was, the Washington Federalist charged on Dec. 8, 1801, an "open and daring insult offered to the Christian religion." Here, for the Federalists, was the same old Jefferson, the same old atheist. Political capital, they concluded, could still be made from sounding the alarm about presidential infidelity.
During the presidential campaign of 1800, Jefferson had suffered in silence the relentless and deeply offensive Federalist charges that he was an atheist. Now he decided to strike back, using the most serviceable weapon at hand, the address of the Danbury Baptists.
*sounds like a certain 700 club demagogue whose intitals are pr dont it?
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