WASHINGTON -- CIA Director David H. Petraeus, the retired four-star general widely commended for his oversight of the U.S. wars in Iraq and Afghanistan, resigned Friday from his position due to an extramarital affair.
"After being married for over 37 years, I showed extremely poor judgment by engaging in an extramarital affair," Petraeus wrote in a letter to Central Intelligence Agency employees.
"Such behavior is unacceptable, both as a husband and as the leader of an organization such as ours."
Petraeus, 60, said President Barack Obama accepted his resignation Friday. White House staff learned about Petraeus's resignation and affair on Nov. 7, the day after Obama's re- election to a second term, according to a person familiar with the disclosure.
Petraeus offered his resignation Thursday in a meeting with Obama at the White House, said the person, who requested anonymity to discuss internal matters.
"By any measure, he was one of the outstanding general officers of his generation, helping our military adapt to new challenges," Obama said in a statement. In Iraq and Afghanistan, the president said, Petraeus "helped our nation put those wars on a path to a responsible end."
Obama said he wishes Petraeus and his wife, Holly, "the very best at this difficult time," according to the statement.
Deputy Director Michael Morell took over as acting CIA director with Petraeus's departure, Obama said.
Petraeus, a graduate of the U.S. Military Academy at West Point, retired from the Army in 2011 to take the helm of the CIA. Prior to that move, he was the top U.S. commander in Afghanistan.
Petraeus, an expert in counter-insurgency tactics, became well known in Wash ington circles during his time overseeing and implementing President George W. Bush's 2007 "surge" of U.S. troops in Iraq. In regular appearances on Capitol Hill, some involving lawmakers questioning both the war strategy and the conflict itself, he garnered support among many lawmakers.
The Senate approved his nomination for CIA director by 94-0 in June 2011.
Sen. Dianne Feinstein, a California Democrat who is chairwoman of the Senate Intelligence Committee, called the resignation "an enormous loss" for the intelligence community and country.
"I wish President Obama had not accepted this resignation, but I understand and respect the decision," Feinstein said in a statement.
"General Petraeus is one of America's most outstanding and distinguished military leaders and a true American patriot," Rep. Peter King, a New York Republican who heads the Homeland Security Committee, said in a statement.
Petraeus leaves an agency embroiled in the fallout from the deaths of four U.S. citizens, including the ambassador to Libya, in a September terrorist attack in Benghazi. Republican lawmakers have been pressing the Obama administration, CIA and State Department for more information about what occurred during the attack.
Petraeus was set to testify at the Senate Intelligence Com mittee next week. He will no longer appear at the Nov. 15 session, according to Brian Weiss, a spokesman for Feinstein.
A fitness buff who earned his Ph.D in international relations from Princeton University, Petraeus had a distinguished 37-year military career. He co-authored the army's counterinsurgency manual, which became the blueprint for forces in Iraq under his leadership.
He also stepped in, at Obama's request, to command the war in Afghanistan after Army General Stanley McChrystal resigned after an embarrassing article in Rolling Stone magazine.
"General David Petraeus will stand in the ranks of America's greatest military heroes," Sen. John McCain, the top Republican on the Senate Armed Services Committee, said in a statement. "His inspirational leadership and his genius were directly responsible -- after years of failure -- for the success of the surge in Iraq."
Petraeus becomes the latest in a line of public figures whose careers were derailed or ended by affairs. Former senator John Edwards, a presidential candidate in 2004 and 2008, acknowledged an affair and fathering a child out of wedlock. Sen. John Ensign, a Nevada Republican, acknowledged an affair with a former campaign staffer and eventually resigned amid a Senate ethics probe. Former New York governor Eliot Spitzer resigned after officials said he cheated on his wife with prostitutes.
Others, including President Bill Clinton, have survived extramarital activities. Clinton denied having an affair with a White House intern, Monica Lewinsky, and was impeached for making false statements to federal investigators. Clinton has returned to the public stage, campaigning for Obama's re-election this year at nearly 30 events.