I wanted to compare the treatment of Aqualad and Wonder Girl in Teen Titans with their adult counterparts in early Justice League, but it took me a while to work up the energy to read the Justice League Showcase collection. Gardner Fox is not my favourite silver age writer, and if there was ever a poll of DC's all time most annoying character, you can bet that Snapper Carr would be a contender.
On the other hand I am surprised how much I warmed up to Bob Haney after a few issues of Teen Titans, and I can hardly believe I didn't like Robert Kanigher when I first encountered his work, so maybe some intense study of early JLA would help me find the fun a third time.
500 pages later I am still not much of a fan of Gardner Fox, but the volume wasn't quite the chore I had expected, and Snapper Carr doesn't appear enough to be more than an irritant. The plots are formulaic and dumb, but provide enough entertainment, often for the wrong reasons, that you don't completely glaze over.
As with the Batman volume, the stories often suffer from the "Schwartz cover" effect. That is, editor Julius Schwartz commissions an exciting cover and then hands it to the writer to tell a story around, but then doesn't seem to care how the cover image is shoehorned in. The result often being that the cover scene is a ludicrously contrived moment in an otherwise unrelated plot. Which is disappointing, as the covers, often very intruiging or exciting, promise so much, but deliver so little.
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But back to my original motivation for reading the book. How does Gardner Fox's treatment of Wonder Woman and Aquaman compare to Bob Haney's use of their counterparts in Teen Titans?
Aquaman is less obviously useless because of the nature of the stories. Where Teen Titans is given a realistic setting, the JLA are usually thrown into a fantasy landscape, so tailoring part of it to suit Fishguy is less blatant. Plus the formula plot usually involves each member of the team being transported to an environment designed specifically for them, either on another planet or an alternate dimension.
Wonder Woman is not singled out in any way. There is even less characterisation in JLA than there is in Teen Titans, which hardly seems possible, but it's true. There are no distinguishing voices, and many of the team are differentiated by a single ability: Aquaman talks to fish, Wonder Woman has a rope, Flash runs fast, Green Arrow shoots stuff. These characteristics are applied to every possible situation. Green Arrow can't put handcuffs on a subdued villain without using a handcuff arrow, Aquaman can't make a cup of tea without the assistance of his fishy friends. Beyond that their abilities are a bit vague.
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It gets so bad that even the villains start to notice.