Editing Trinity (nuclear test) (section)

===Official notifications===
The results of the test were conveyed to [[Secretary of War]] [[Henry L. Stimson]] at the Potsdam Conference in Germany in a coded message from his assistant [[George L. Harrison]]:

{{blockquote|Operated on this morning. Diagnosis not yet complete but results seem satisfactory and already exceed expectations. Local press release necessary as interest extends great distance. Dr. Groves pleased. He returns tomorrow. I will keep you posted.{{sfn|Jones|1985|p=517}}}}

The message arrived at the "Little White House" in the Potsdam suburb of [[Babelsberg]] and was at once taken to Truman and Secretary of State [[James F. Byrnes]].{{sfn|Alperovitz|1996|p=240}} Harrison sent a follow-up message which arrived on the morning of July 18:{{sfn|Alperovitz|1996|p=240}}

{{blockquote|Doctor has just returned most enthusiastic and confident that the little boy is as husky as his big brother. The light in his eyes discernible from here to Highhold and I could have heard his screams from here to my farm.{{sfn|Jones|1985|p=517}}}}

Because Stimson's summer home at Highhold was on [[Long Island]] and Harrison's farm near [[Upperville, Virginia]], this indicated that the explosion could be seen {{convert|250|mi}} away and heard {{convert|50|mi}} away.{{sfn|Jones|1985|p=518}}

Three days later, on July 21, a 13-page report written by Groves arrived at Potsdam via a courier. It stated:

{{blockquote|At 0530, 16 July 1945, in a remote section of the Alamogordo Air Base, New Mexico, the first full scale test was made of the implosion type atomic fission bomb. For the first time in history there was a nuclear explosion. And what an explosion! ... The test was successful beyond the most optimistic expectations of anyone.{{sfn|Sherwin|1987|p=308}}}}

It continued on to estimate the yield of the test (15-20 kilotons) and describe the effects vividly. Stimson took the report to Truman, who was "tremendously pepped up by it." [[Winston Churchill]], who observed Truman's newly confident approach with the Soviets the same day, concluded that he had become "a changed man" as a result of the news.