Texans definitely have a swagger. Even if you spoke to no one and only observed the signs, you'd still get a sense of their confidence.
In addition to this colorful warning at a rest area, scores of no-litter signs proclaim, "Don't mess with Texas."
I even saw a sign on a desert highway in the panhandle that said simply: "MAINTAIN YOUR VEHICLE."
Don't think a Texan is gonna come bail out your behind!