I think Americans are taking hops to a whole new level. To me, beer is and should be a malt-based beverage.
I think that this is because American malts tend to be drier and "breadier" than continental malts. Also, most American beer drinkers are coming to craft beer having first experienced thin-bodied, effervescent, rather dry light lagers. Lots of hops on top of relatively low malt flavor is less of a transition than chewy, sweet, multi-layered malt character. Also, to be honest, a sweetish, malt-forward style beer isn't something you want to drink as a "lawnmower beer" on a hot day, and for most of the U.S. it gets damned hot for much of the year.
Even so, I don't get the American love affair with citrusy and piney hops. I go for the English and Noble types myself.
Even though the ABA guidelines say as much, many judges just see "American" in the name and assume that means that the beer should taste like a West Coast double IPA. That's wrong and it's lazy judging. Instead, it's more about the yeast and malt character and the balance of malt to hops.
But, as Anthony said, if you're brewing for competition, you want to make a beer which the average judge will recognize as being distinctly American. Also, typically ABA tend to get judged last in the American Ale category. That means that many judges will be mentally comparing ABA to American Pale Ales whether they realized it or not.
In a world with more perfect BJCP style guidelines, APA would be its own category given its popularity. ABA and American Amber would be off in their own little niche, perhaps combined with the English Brown Ales.