You're talking to somebody who practically ate the stories of Dr. Seus, and the Lorax in particular was one of my favorites when I was a kid. So I got the joke pretty well... Yet it also seems like a statement about guns....
The trees will still be harmed
The onceler too is armed
And his army will fire at will
When they see the Lorax they'll shoot to kill
Now the Lorax could be armed
But against a whole army, he'll won't just be harmed
Don't get it high in your head
The Lorax is only certain to be dead :P