As a transplanted New Mexican, I've often wondered why New Mexico and Arizona are so different. Climatically, a difference in altitudes accounts for Arizona's saguaro cactuses and New Mexico's lack thereof. The attitudes, however, have been more puzzling. These are two states that entered the Union together, in 1912, the last before Hawaii and Alaska.
Here's some Arizona history I wasn't aware of that explains some of it. Now I'm wondering why New Mexico didn't have to prove its white bona fides when it entered the Union.