"Truth, Justice AND the American Way"?
Solution 1:
There's actually a common standard in interpretation of lists for poetics, scripture and the law, which says that the meaning of a word within a list should be taken in relation to the other items in the list. There's another standard that holds that no interpretation is valid that makes any wording mere repetition. In that light, I'd say that the original Superman slogan portrays truth, justice and "the American way" as distinct but related concepts.
Solution 2:
The phrase "red, white, and blue" presents a series of elements that are equal in specificity and are non-overlapping. Each of the three elements defines a separate color, and the reader can reasonably infer that some sort of opposition in meaning to the other two colors justifies the inclusion of each.
However, the elements included in a parallel series can overlap without harming the coherence of the construction. The phrase "life, liberty, and the pursuit of happiness," for example, doesn't imply that those three ideas are entirely separate from one another, or that one necessarily excludes another. In fact, the parallelism in that example runs successively from most general ("life") to somewhat more specific ("liberty") to most specific ("the pursuit of happiness"). Once the reader recognizes the progression that is built into the parallelism, the phrase makes sense without any need to find the negation of one term in the others.
But parallel constructions can run into coherence problems when the elements listed in the parallel series are neither of equal weight nor presented in a recognizable order. That situation, I think, is what leads some listeners to misinterpret the phrase "for truth, justice, and the American way."
Consider this example:
I like pie, ice cream, and sweet desserts.
A reader might reasonably respond to this sentence by asking, "But aren't pie and ice cream sweet desserts? What kind of distinction is the author trying to make between pie and ice cream on the one hand and sweet desserts on the other?"
The problem is that "pie," "ice cream," and "sweet desserts" (like "truth," "justice," and "the American way" in the OP's example) appear as elements in a parallel structure that doesn't signal any difference in their order of magnitude or complexity. And because "pie" and "ice cream" (like "truth and "justice") seem as naturally coequal as "red" and "white" in the "red, white, and blue" example, readers are set up to expect the third term in the series to be equal to the other two—an expectation that the third term does not fulfill. The faultiness of the wording thus lies in the author's failure to clarify how the parallel elements are to be understood in relation to each other.
One way to clarify the sense of the "sweet desserts" sentence is to warn readers of the impending shift in specificity:
I like pie, ice cream, and (in general) all sorts of sweet desserts.
In the "American way" example, the author expects listeners to recognize "truth" and "justice" as being among the virtues that inform the American way of life; but the slogan as formulated doesn't give the hearer any structural basis for achieving that recognition. To make the intended relationship of the parallel elements clear, the author could have offered wording along these lines:
For truth, justice, and the other civic virtues that characterize the American way.
or:
For truth, justice, and (what amounts to the same thing) the American way.
On the other hand, if "the American way" really was supposed to be a specific virtue coequal with "truth" and "justice," and not a composite of those virtues and others not named, the author could have chosen a less vague term to indicate what he or she deemed that virtue to be. For example:
For truth, justice, and rugged individualism.
But being a sloganeer, the author didn't want to clutter the slogan with explanations or qualifications. Perhaps that disdain for subtlety is another aspect of the American way.