That Laurence and the Times kept their end of the bargain is amazing. Sure wouldn't happen today.
You're right, of course, about the NYT, given their more recent secret-spilling done with apparent complete impunity. However, since it was wartime and involved the ultimate weapon, it's not unlikely the government added a thick, heavy stick with that carrot (It's not the carrot and but or the stick).
Says here that Laurence was the only journalist to witness Trinity AND Nagasaki.
http://research.omicsgroup.org/index.php/William_L._Laurence
Also:
In May 1940, Laurence published a front-page exclusive in the New York Times on successful attempts in isolating uranium-235 which were reported in Physical Review, and outlined many (somewhat hyperbolic) claims about the possible future of nuclear power.[3] He had assembled it in part out of his own fear that Nazi Germany was attempting to develop atomic energy, and had hoped the article would galvanize a U.S. effort. Though his article had no effect on the U.S. bomb program, it was passed to the Soviet mineralogist Vladimir Vernadsky by his son, a professor of history at Yale University, and motivated Vernadsky to urge Soviet authorities to embark on their own atomic program and established one of the first commissions to formulate “a plan of measures which it would be necessary to realize in connection with the possibility of using intraatomic energy” (no full-scale atomic energy program began in the Soviet Union until after the war, however).[4]
In April 1945, Laurence was summoned to the secret Los Alamos laboratory in New Mexico by General Leslie Groves to serve as the official historian[5] of the Manhattan Project. In this capacity he was also the author of many of the first official press releases about nuclear weapons, including some delivered by the Department of War and President Harry S. Truman. He was the only journalist present at the Trinity test in July 1945, and beforehand prepared statements to be delivered in case the test ended in a disaster which killed those involved. As part of his work related to the Project, he also interviewed the airmen who flew on the mission to drop the atomic bomb on the city of Hiroshima, Japan. Laurence himself flew aboard the B-29 The Great Artiste, which served as a blast instrumentation aircraft, for the atomic bombing of Nagasaki.
And finally the answer to the BIG question.
http://blog.nuclearsecrecy.com/2012/09/05/beer-and-the-apocalypse/
Will beer survive the apocalypse?