As recently as the early 2010s, when I first started writing about Texas politics, there was a sense that folks had to climb a ladder to reach the highest offices in the state. You ascended from the Legislature to a lesser statewide seat—comptroller, land commissioner—kept your nose clean, built your Republican credentials, and then moved up to a bigger one. Key to taking the final step was demonstrating that you could handle responsibility and not embarrass the donors and friends who had invested in your rise.That’s what Rick Perry did: In 1991, he moved from the state House to do a passable job as agriculture commissioner and then made it to lieutenant governor in 1999, just in time for Dubya to take the White House…