Besides silk, the Chinese also exported (sold) teas, salt, sugar, porcelain, and spices. Most of what was traded was expensive luxury goods. This was because it was a long trip and merchants didn't have a lot of room for goods. They imported, or bought, goods like cotton, ivory, wool, gold, and silver.
My personal opinion would probably be a nurse. The reason being is even if I was not allowed to physically help out in the war, I would still feel like I was making a difference.
What injustices are you trying to find out exactly?