I think paying your respects to the men and women in uniform is just fine. Wearing a red shirt is a tad absurd.
Occasionally, these sorts of symbols catch on, while I'm sure most of the time, they fail. Here in OKC, following the OKC bombing, we all drove around with our lights on for months as if to say "I remember" or to show solidarity or something like that. As with all fads, that died. I guess that means we forgot about the bombing??
Didn't the bloody shirts help put Ulysses S. Grant in office?
That worked out well