“Don’t Mess With Texas” is the famous 1986-86 anti-littering campaign. “Don’t mess with Texas—we’re armed” is an unofficial variation (from at least 1997) that has been printed on images.
   
   
Rejected State Mottos
TEXAS:       
Si Hablo Ingles
See, EVERYTHING is bigger in Texas!
Don’t Mess with Texas—We’re Armed
     
Google Groups: alt.callahans
Newsgroups: alt.callahans
From: .(JavaScript must be enabled to view this email address)
Date: 1997/04/02
Subject: Recycled Humor #5
 
>    >  TEXAS:
>    >  Don’t Mess with Texas—We’re Armed >
     
5 April 1997, The Post and Courier (Charleston, SC), “What’s the best pick for motto on license tag?” by Elsa McDowell, pg. 1:
Now that the state license tag dilemma has been resolved (families-first versus smiling faces) Howard Peckenpaugh allows as how other states also have faced difficulty choosing their mottoes.
 
He sends a list of state mottoes that were rejected:
(...)
Texas: Don’t Mess with Texas - We’re Armed
 
Twitter
joshtrefethen
@joshtrefethen
Don’t mess with Texas we’re better armed than most http://twitpic.com/23ibq
3:36 PM · Mar 14, 2009·Twitter Web Client
   
Twitter
𝓢𝓱𝓮𝓵𝓵𝓲𝓮 ✌🏻❤️🎶
@dirtroaddiva1
Don’t mess with TEXAS.  We’re armed. 
#BadMottosForStates
4:20 AM · Mar 21, 2016·Twitter for iPhone
   
Twitter
David J. Brewer
@davidjbrewer
Replying to @VivaLaAmes11
Don’t mess with Texas. We’re armed and ready.
8:41 AM · Jun 13, 2017·Twitter for iPhone