Wasn’t most of the silk used in Europe produced in Italy and France, though? Added together they weren’t that far off from China (which also had a huge domestic market). India was also a major exporter so clearly Britain had the option to expand “domestic” production or buy more silk from Italy (importing from China was presumably just cheaper).
European silk production collapsed in 1849 due to some still not well understood disease but that was quite some time after the first Opium War.
Burning silk (and other organics) makes cyanide. I have no idea if this can be weaponised.
Silk is a defensive weapon. Or, maybe silk cords power bows or Ballista?
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