This gave me a flashback to a patrol of BritCon West west of Nicosia after the war. A company of Paras observed the Green Line from Nicosia Airport westward out to DanCon. They were housed (as were all UNFICYP troops) in a string of bungalows deserted by fleeing Turkish Cypriots during the war.
We patrolled the Green Line in our Ferrets and called into bugalows and watchtowers as required. On one particular occasion I asked the Paras politely if I might use the cludgie rather than pissing in the desert. I passed two posters, evidently done by the platoon artist. One was on the cludgie and stated:
OUR AIM IS TO KEEP THIS TOILET CLEAN
YOUR AIM WILL HELP
The other was on the wall near the WC and showed planet earth. Somewhere in the Northen hemisphere was a Platoon Sergeant screaming into a slit trench:
"DIG IN! DEEPER!"
and on the opposite side of the world was an entrenching tool breaking the surface.