Even the classic WB cartoons were aimed at adults, although you must be familiar with old time radio programs and 1940s politics to appreciate a lot of the jokes today.
Cartoons have never been aimed solely at children.
Yep, if you've ever seen them (now removed by our wonderful Gov't. sensoring for PC) there are old Bugs Bunny cartoons that were VERY political propaganda types.
1. Bug Bunny fighting the Japanese, "Bugs Bunny vs. The Japs" (close to actual title)
2. Bugs Bunny fighting the Nazi's (I don't recall the name)
I have these in Divx from Ebay, I could not believe some of the content on the Japanese episode!