americans hostile to knowledge, but what does this excerpt say about nytimes readers?

reddit pointed me to a recent New York Times article on anti-intellectualism in America. OK, so it may not be the most original subject, but certainly worth another analysis.

Author Susan Jacoby got the idea for her recent book, "The Age of American Unreason", on 9/11. The Times reports:
Walking home to her Upper East Side apartment, she said, overwhelmed and confused, she stopped at a bar. As she sipped her bloody mary, she quietly listened to two men, neatly dressed in suits. For a second she thought they were going to compare that day’s horrifying attack to the Japanese bombing in 1941 that blew America into World War II:

“This is just like Pearl Harbor,” one of the men said.

The other asked, “What is Pearl Harbor?”

“That was when the Vietnamese dropped bombs in a harbor, and it started the Vietnam War,” the first man replied.

At that moment, Ms. Jacoby said, “I decided to write this book.”
I couldn't help but wonder why journalist Patricia Cohen would preface the anecdote by explaining that Pearl Harbor was "the Japanese bombing in 1941 that blew America into World War II."

Along with ruining the punchline, doesn't this imply that there'd be New York Times readers who'd have missed this historical blunder?

Surely this was done as a courtesy to the many non-U.S. readers who may not (although likely do) know about this significant event in our country's history as well as for those Americans who'd have just scratched their heads. It just seemed rather ironic given the context.

Although, I wonder how many Americans back in 1941 were thinking of the similarities between between that infamous December day and the Battle of Port Arthur...

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