In a speech in Albuquerque yesterday, John McCain introduced a new line of attack against Barack Obama, namely that he came “out of nowhere” and we don’t really know who he is. When he asked the key question, “Who is the real Barack Obama?” a member of the audience yelled, “Terrorist!”

Although the word “terrorist” clearly caught McCain by surprise, I think it’s remarkable that he didn’t stand up for Obama and defend his honor, as one would expect from a man who gives the importance to honor that McCain does. He just kept going, as if he hadn’t heard.

Meanwhile in Clearwater, Florida, Sarah Palin was pursuing a parallel line of attack, raising Obama’s past association with Bill Ayers, an education theorist and social activist who was once a member of the Weather Underground. Here’s how her speech was reported by Dana Milbank of the Washington Post.

“I was reading my copy of the New York Times the other day,” she said.

“Booooo!” replied the crowd.

“I knew you guys would react that way, okay,” she continued. “So I was reading the New York Times and I was really interested to read about Barack’s friends from Chicago.” […]

“Now it turns out, one of his earliest supporters is a man named Bill Ayers,” Palin said.

“Boooo!” said the crowd.

“And, according to the New York Times, he was a domestic terrorist and part of a group that, quote, ‘launched a campaign of bombings that would target the Pentagon and our U.S. Capitol,'” she continued.

“Boooo!” the crowd repeated.

“Kill him!” proposed one man in the audience.

I don’t know which is scarier, the angry crowd or Palin’s unblinking faith in her own beliefs. She gives me the impression that she is someone who, since childhood, has never really questioned what she was told. The saying “Ignorance is bliss” was invented just for her. She has absolute confidence that she is right, and on top of that, a kind of contempt for people who have doubts or ask questions.

This contempt has been apparent since her acceptance speech at the Republican national convention, when she slammed Obama for the introspective temperament revealed in his memoir Dreams from My Father, saying, “The American presidency is not supposed to be a journey of personal discovery.”

The United States is the only nation to have ever had a political party called the Know-Nothings, and it is the sentiments of such people that McCain and Palin are hoping to stir up between now and election day, casting doubts on Obama as someone who came from a foreign land, who isn’t one of us, and who we supposedly don’t know even though he’s been in the spotlight since 2004.

Nate Silver, whose polling analysis website fivethirtyeight.com is the best resource for understanding the current state of the election, recently wrote an article explaining why the attacks probably won’t work. He gives two reasons: middle-class voters have already made up their minds that Obama is “their guy” on the most important issue of this election, the economy; and McCain’s “brand” is all about honor and integrity, but that brand will be damaged if he descends into the gutter of hate-filled attacks. Meanwhile, Obama keeps rising in the polls, so early indications show that Nate is right.

I would add two more reasons: Obama is pretty well immunized by now against attacks on his character, because the American people have seen him respond calmly under pressure, while McCain is the one who seems erratic and radical; and most Americans are sick of manipulation based on fear, having seen where it leads, to war and economic collapse, so they are eager to reject it on election day. It didn’t work in 2006 against Congressional Democrats, and it won’t work against Obama unless he does something completely out of character between now and November 4 to destroy people’s trust.

If that is all McCain has to hope for, he has lost the election.