[erlikhan]

Answer can be based on simple assumptions (I guess). Japanese kept their swords as an ancestral memory through generations, in fact they could do it. They didnt make continuous wars with other nations, didnt invade other countries and get invaded by others hundreds of times till the end of sword era, and their local wars didnt have cannon explosions helping swords to return safely from the wars . Swords of Islamic countries suffered these facts at their maximum ,were used to their full capacity,got worn and destroyed. In Turkey, most of any kind of edged weapons found were picked to plunder or destroy by invaders, or used by militia to defend their homeland in neverending invasions of early 20th c till 1922. over the country,even picked by the regular troops from civilians when there is no regular weapon around to use. In 18th and 19th c. periodically, when an economical crisis occured, State was ordering the return of silver items to the treasury, to melt them and mint coins. This was causing gorgeous weapons loose their mountings and become simple pieces of iron, very desirable to get rid of. Plus as they were part of European history too, they got popular earlier than Japanese swords , causing many to go into museum and private collections, and stay out of the market forever.