sitting silently in a classroom for seven minutes after learning the country was under attack on Sept. 11, 2011, but his former chief of staff isn't one of them.

Andy Card told CNN's Anderson Cooper Sunday that he was "pleased" with how the former president responded.

"I was a little bit surprised that he reacted so calmly when I said words that were so outrageous, but I actually was pleased with how he reacted," Card explained.

"I said, 'A second plane hit the second tower. America is under attack,'" he recalled. "And then I stood back from him so that he couldn't ask me a question. And I kind of thought he might turn and look at me and start to talk, and I didn't want want him to do that. So, I was pleased that he focused on the students."

In 2007, HBO's Bill Maher called for Bush to be impeached over his initial inaction that day.

"What could be more important for a president of the United States to do than to react at that moment when he hears the words, 'The country is under attack'?" Maher asserted.

For his part, Bush has argued that he was trying to "project a sense of calm."