First, Obama lost because he, like virtually the entire left, lives in a left-wing bubble.
Left-wing academics live in this bubble. There is no greater uniformity of thought than at our universities; their much-ballyhooed commitment to diversity is about race and ethnicity, not about ideas.
So, too, the great majority of news media people live in the same bubble, the left-wing herd that covers national and international news. Reading The New York Times, The Washington Post, the Los Angeles Times or Le Monde or listening to the BBC is essentially reading or listening to the same selection and presentation of the news.
One reason leftists talk to, read and listen to only fellow leftists is that they are certain that there is no other way to think rationally, compassionately or morally. Therefore, there is no reason to debate conservatives, let alone expose oneself to their ideas.
Obama is a man of the left. Leftism is his Weltanschauung, his value system, his way of understanding the world. Every one of the president's mentors whom we know about was a leftist, usually a radical leftist. The church he was married in and the pastor he adored were leftist. His work -- "community organizer" -- was left-wing work.
When you live in a bubble -- be it religious or political -- you cannot successfully debate opposing views. You're not even familiar with what those opposing views are. This debate was the first time in Obama's presidency -- if not his life -- that he had to defend the policies he believes in against an articulate conservative.
The second reason for his defeat was that Obama lacked two things that have been essential to his popularity for the past four years.
One was a teleprompter. Most people would sound articulate if they could rely on teleprompters to speak words they and/or others wrote. But there were no teleprompters last Wednesday night.
Were a Republican president as dependent on a teleprompter as this president has been, the media constantly would report -- and mock -- the fact.
Which brings us to the news media's protection, the other thing the president was deprived of at the debate.