An editorial in the New York Daily News makes a case that it should be, since the document is among “the seminal American endorsements of religious freedom.”
Some six decades ago, businessman Morris Morgenstern purchased the letter and later gave title to a personal charity, the Morris Morgenstern Foundation.
The foundation, in turn, loaned the document to B’nai B’rith International for display in a museum that closed about 10 years ago.
Since then, Washington’s words have been in storage and the foundation has declined to cooperate with efforts by the Library of Congress, the National Museum of American Jewish History and others to return this letter to wonderful public display.
While the foundation’s ownership of the document is unimpeachable, his inspirational words on paper are part of the American patrimony.
You can read Washington’s letter in its entirety here.