Abraham Lincoln, regarded as one of America's greatest presidents, said: "Nearly all men can stand adversity, but if you want to test a man's character, give him power."
We ask much of our presidents. We want people of character who possess a strong will. They must also be charismatic individuals who challenge and inspire.
Above all, they must be leaders.
Even great leaders will fail, but we can forgive them if we know that they did their best, that their sense of duty was greater than their concern for personal safety, popularity or political expedience.
What we don't like is deception.
President Richard Nixon is the poster child for deception. He put himself above the law during the Watergate scandal and obstructed justice.
The cover-up was worse than the crime, and the duplicity and obfuscation changed the way we view the presidency.
President George W. Bush did not set out to deceive about weapons of mass destruction in Iraq, but in hindsight we know there was an unhealthy disregard for legitimate questions about the evidence.
The confidence with which the Bush administration pushed the war, combined with the failure to prepare adequately for post-Saddam Iraq, caused many Americans to question his leadership.
Now we have the Sept. 11, 2012, attacks in Benghazi that killed four Americans, including Ambassador Christopher Stevens.
Gregory Hicks, Stevens' deputy in Libya, testified on Capitol Hill that they knew immediately that the attack was a coordinated terrorist assault, not a spontaneous demonstration triggered by a YouTube video.