Well, I can bet the knife the US Marine in the picture was wearing a REAL ONE.
They became illegal at some point do to the three sided blade. When a soldier was stabbed with one, the wound would not close up, so they became a banned weapon, along with the poison gas. At that point many of the daggers were destroyed or went into private collections. But the demand got going by WWI and WWII collectors so many fakes appeared.
Banning those weapons doesn't make much to much sense to me, since you can still burn someone alive with a flame thrower or blow them to pieces with a grenade, but who ever said war made sense ... :redface2:
--- LaRRy