Reply #2: But there's one telling detail I unearthed in the LBJ archive in Austin.

[Jefferson23]

During the preparations for Mohieddin's visit, Eugene Rostow wrote a memo suggesting that the US notify Israel of the "secret" meeting, since "my guess is that their intelligence will pick it up". And indeed the US did notify Israel of the June 7 meeting, an apparent last-ditch effort by Nasser to avoid war.

But of course Mohieddin never made it to Washington. By the time of the scheduled meeting, it was already day three of the Six-Day War. The Israelis had captured Sinai, Gaza and the West Bank, and Arab forces were beating a humiliating retreat.