In fact, if one were to burn a flag with 50 stars arranged in the shape of a Swastika, not only would it be an even more effective protest, but it wouldn’t violate the law.
[Hijack]I just read something I did not know for certain before. Any flag recognized as an “official” U.S. flag remains official even after it has been superceded.[/hijack]
I would presume that altering an existing American flag would be illegal (but of course, there are no penalties given for violations in the U.S. Flag code). You might be better off making your own, if you want to be technically legal in every way. As long as it did not conform to the legal dimensions of the flag*, nor accurately represent any recognized historical flag, you would be within the letter of the law, and the flag, though similar in design to the U.S. flag, would not actually be an official flag. You can do anything you like with such a flag as long as it is not illegal to do likewise with a similarly-sized tablecloth.
Unless I’m missing something from the description above, I would guess that the pattern of stars does not have an “official” standard design, and the regular grid we see is merely the preferred arrangement. Therefore, laying the stars in a nonstandard pattern, even a swastika, would not make the flag unofficial.
Altering the proportions given above, as long as it does not result in an accurate copy of any previous official flag, would result in an unofficial flag that would not be covered by the U.S. Flag code with regard to how it should be handled, displayed, etc. (if I’m interpreting the laws correctly – IANAL!)
Last I heard, it was still perfectly legal to burn any US flag, official or not. That whole First Ammendment thing. US Flag Code is only legally binding on flags owned by the United States government, I believe. And you are correct about all previous versions still being recognized.