Hops die back to the root every year, so no big deal there. A barrel is ok (probably better that the all-natural concrete that passes for soil in Tucson), but it will need frequent watering.
Tucson's weather isn't much harsher than the weather in the Yakima, WA area. Hot, dry & sunny is what hops like.
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"
"I would like to die on Mars, just not on impact." Elon Musk