The Arizona Department of Transportation continues to make plans for the fabled Interstate 11, announcing a $155 million investment into the stretch of highway from Phoenix to Las Vegas. The plans, for what is now known as U.S. 93, have been in the making for years, with several more to go. Meanwhile, the nerve-rattling, headache-inducing, traffic-clogged two-lane stretches from Tucson to Phoenix that are much of Interstate 10 aren’t getting much thought. The issue is that touted improvements to U.S. 93 are part of a larger plan to build a dedicated trade corridor between Mexico and Canada, running right through...