But the invasion never came. For years,American scientists had been developing a secret weapon,the atomic bomb.

VOA: special.2011.06.23

The Manhattan Project,when they created the atomic bomb and whether or not you agree with the Manhattan Project normatively.

曼哈顿计划中，他们创造了原子弹,无论你是否同意,这计划。

哈佛公开课 - 幸福课课程节选

He and other refugee scientists were worried that Germany was working to develop an atomic bomb.

VOA: special.2009.06.14

Of course, the atomic bomb was one of the greatest U.S. secrets of World War II.

FORBES: Alleged White House Leaks

During active service, Wyllie visited Hiroshima and saw for himself the impact of the atomic bomb.

BBC: Obituary: George Wyllie

In 1952, the first British atomic bomb was detonated on the Monte Bello Islands off north-west Australia.

CNN: Friday,