Why Btonze Age?

[Minimalist]

japanese armor works somewhat differently from rigid armor like plate armor or linen cuirass.  Japanese armor often consists of individual lacquared tiles that maybe semi-rigid, but that are hold in place by a elastic webwork of cords.  So the energy of the impact is absorbed over a large area.  The airspace behind the armor probably allow the surface layer to move back and stretch the cords without bruising the flesh behind it.  

Silk can also be woven very tightly, to the point where just a handful of layers of silk can present a waterproof and airtight barrier.   So silk probably works even better than linen if glued into little plates.

You know, that's really a good point.  Armor, in order to justify the cost of production and the impact on movement, had to work.  That is to say that no one would have created it/ worn it if it did not stop the primary threat faced by a soldier.  Think about the "armor" shown in the Star Wars movies:



It is apparently ineffective against ray guns so why wear it?  Because the producer thinks it looks cool?  That would not cut it in real life.  As European armies moved to muskets armor for the soldiers dwindled away because it was not going to be effective against musket and cannon.  Vestiges survived in officer's gorgets and certain heavy cavalry units like the cuirassiers.



So, yeah.  If armorers went through the trouble of making something you can bet your ass that it served an actual military need at the time and was not a mere decoration.