Serious? Its not a lie unless you believe it, right? If Obama didnt realize he couldn't deliver what he promised, then he had no idea what it takes to be president.
There are several situations where the government may be involved in sensitive negotiations or missions where it's not just enough to refuse to answer or especially to say that something is classified. For example the Osama Bin Laden raid. If people involved such as the President, Secretary of Defense, Secretary of State, and etc. are asked by reporters if something like that was in the works while planning and execution was going on silence or stating that it's classified might either lead to rampant speculation that could harm the mission or tip off Al Qaeda, the Pakistan military or other parties that something is going to happen even if they don't know the details. In a case like that it might be better to release a cover story or something else to direct attention away from what is actually going on. In the case of the Osama Bin Laden raid. Obama released his long form birth certificate the day before the raid happened which absorbed the news cycle. In another example where government officials essentially lied was in the case of the Stealth fighter. There had been a lot of speculation about what the fighter looked like and people in the military leaked images of a rounded frisbee like craft. The actual fighter didn't look much like the that. This took attention away, and potentially for foes and rivals to start developing anti-stealth technology, until the fighter was actual developed and put into service.
Everyone who works in law or politics has to lie, because you have too many stakeholders with differing interests to be both truthful and actually get anything done. Pelley's a great journalist and it was a fair question, but that's a completely fair answer as well. The idea of a wife or mother having enough autonomy or self-interest to assert any kind of discretion or craft their own narrative is still too jarring for a lot of men.
Oh, Hillary. <iframe width="560" height="315" src="https://www.youtube.com/embed/-dY77j6uBHI" frameborder="0" allowfullscreen></iframe> Every politician lies, but few as much as Hillary, and few as little as Bernie. You might not care about that, but it's really hard to dispute that. Even those who support her tend to admit she's obviously being dishonest but it's just part of the territory. Which is fair, if there's no reasonably different alternative.