"Don't ever make the mistake most New Yorkers do, of underestimating Chicago," warns Jeffrey Archer in his book Kane and Abel. This quote suggests that Chicago is often overlooked or underestimated by others, especially by New Yorkers. The city is often seen as less significant or just a small part of a larger landscape, but this underestimation is a mistake that should not be made.

Archer emphasizes that Chicago holds its own importance and shouldn't be dismissed. The analogy compares New York to an envelope and Chicago to a postage stamp on it, implying that Chicago is merely a small addition to the big picture represented by New York. Recognizing Chicago's significance is crucial, as underestimating it leads to a misunderstanding of its true value and influence.