Geometrical Patterns of State Names

Most people are reasonably familiar with the two-letter abbreviations for state names introduced by the U.S. Postal Service a number of years ago. These abbreviations have occasionally been the subject of word play in past Word Ways issues: I connected them in a cross-word-style array in February 1976, Darryl Francis constructed words out of them in May 1976, and Philip Cohen programmed a computer to find a maximum-length chain of overlapping abbreviations in February 1977