Primitive working "chameleon" technology is being researched in many places. One sample link talking about such is:
http://news.nationalgeographic.com/news/2006/05/060525-invisibile.html
Note that this is National Geographic.
I would also like to point out that David and Dan have made it clear in the latest book that Confederation chameleons do not, strictly speaking, make one invisible. These high tech garments try to duplicate the scenery on one side of the garment on the opposite side. This approaches invisibility in many situations.
There is no reason to imagine that this technology is impossible.
Not to rag on Dan and Dave but my first thought was Chameoline Cloaks from Dan Abnett's Gaunt's Ghosts books..... (Just cuz they want to make cloaks first)
Doesn't matter... If I know the Marines... even if this was highly possible in at least the near future... USMC wouldn't have the money for it....
But it'd be cool... But you'd have all those problems of finding each other without IR or UV equipment....
I prefer the Last Chancers more, but you do have a point.