This was 1957 and Oppenheimer had already had his problems, lost his security clearance. But the previous spring, a recruiter had come around to Harvard from Los Alamos and said they were looking for people to spend the summer at Los Alamos, and my name came up. And they asked whether I'd like to spend the summer at Los Alamos. I said yes, I'd like that. Sure, that'd be great.

So the first thing was I had to get a Q clearance. And this is a serious business, a Q clearance. I think I had the form that I filled out in the day, in which I put down practically every residence I ever had for the last… practically all my life. And the FBI came, and they interviewed neighbours and so on and so on. Years later, I thought I'd write something for The New Yorker on the process of getting a Q clearance, and I was going to call it Friends and Neighbours, because I thought all of my friends and neighbours had probably ratted on me. And so I used the Freedom of Information Act to get my FBI files, and nothing came and nothing came.

By that time, I had seen Senator Moynihan a couple of times, and one time I told him the problem, and he said, 'Well, I'll look into it'. Then the files came and they were all redacted. Anything that was of any interest had a huge black line through it, so I have no idea what anybody said.

 I was mainly worried about my Aunt May. She was, in the day, a very intelligent communist, and she was… I just don't remember the party, but she subscribed to the Daily Worker and she was always talking about the bosses. But she was a very intelligent woman, and when Russia went bad, invaded things, one thing, she dropped out of that. So I thought, well, they're going to find Aunt May and they'll find that she had a subscription to the Daily Worker, and there will go my Q clearance.

And either they didn't find Aunt May or they didn't care. Whichever. I got my Q clearance.