Aug 2: The letter is believed drafted by the Hungarian Jewish expatriate nuclear physicist Leó Szilárd, in consultation with fellow physicists Edward Teller and Eugene Wigner.
…for review and potential signature by hitherto “pacifist” Einstein. Einstein reviewed the matter carefully, and was a “GO.”
The key and pivotal “Letter” alerted Roosevelt to the imperative of researching, then potentially building, an atomic bomb to preempt Hitler.
The “Letter” was delivered – and summarized verbally – personally to Roosevelt, Oct 11 (over two months after signature) because of Roosevelt’s pre–occupation with
Hitler’s September 1 invasion of Poland.
It was delivered/articulated by Alexander Sachs, a high–level multi–hat advisor to the White House and Cabinet. Upon hearing the Sachs summary, Roosevelt authorized the Uranium Advisory Board (see Trinity Test below in July, 1945).
The Sachs “presentation” would thereby alter the history of the planet.