Colorful Stickers on Cars, Meaning What?

For probably two or three years, I've been seeing these bumper-stickers with green, and yellow and red vertical stripes/bars and I've been wondering what the significance and meaning is. I've asked people who I thought might know, I've even looked it up on websites that sort symbols and their meanings, but to no avail.

You've probably seen it... Looks like this:Then, out of the blue, today I follow two separate cars with that sticker/symbol and the words "Vietnam Veteran" directly under the symbol on the sticker. Now, why didn't they think to tell us years ago? Apparently, it's designed based on what the service medal looks like for those who served in Vietnam.

It's nice to have finally figured that out. =)