According to the Washington Post, Petraeus was hoping to keep his job as CIA Director and thought the affair would not become public knowledge:
But some of his closest advisers who served with him during his last command in Iraq said Monday that Petraeus planned to stay in the job even after he acknowledged the affair to the FBI, hoping the episode would never become public. He resigned last week after being told to do so by Director of National Intelligence James R. Clapper Jr. on the day President Obama was reelected.
“Obviously, he knew about the relationship for months, he knew about the affair, he was in it, so yes, he was not going to resign,” said Peter Mansoor, a retired Army colonel and Petraeus’s executive officer during the Iraq “surge,” who spoke Monday with the former general for about half an hour. “But once he knew it was going to go public, he thought that resigning was the right thing to do. There is no way it would have remained private.”
So Petraeus was pushed and didn’t simply decide to resign. In the aftermath of Benghazi he was a desperate man who realized the White House held his future in their hands. No wonder, against all the evidence, he told Congress in the aftermath of Benghaz on September 14th that the cause of the attack was the Mohammed video.,the Administration fable. The motto of West Point is Duty, Honor, Country. While betraying his marriage vows, Petraeus managed to betray all three in his desperation to keep his career. Completely contemptible.
Update: Hattip to Allahpundit at Hot Air. Petraeus allegedly gave an indication after his briefing to Congress, to one of the members of Congress, on 9/14/12 that the Administration’s Mohammed video line was hogwash:
Final point, though, he may have been under pressure, as Charles says, to go along with the administration line on September 14th about the video, which he knew was not true. Someone else told me that General Petraeus, on the Hill that day, Director Petraeus I should say, said privately to one of the members of Congress, said, “This is what happened in Benghazi,” he said, “Do you want the official line or do you want the real truth?” So I think he knew that he was not telling the full truth. He is, on the other hand, the CIA director. They were involved in some pretty complicated things, perhaps, in Benghazi. To be fair to him, maybe he thought that national security required him not to fully spill the beans and to kind of go along with a line that was otherwise politically convenient for the administration.
The eventual testimony of Petraeus, under oath this time, as he was not on 9/14/12, should be very interesting indeed.