By George, I think I've got it!

I am struggling to see the connection the Chinese are seeking to make between our wearing of poppies to remember our war dead, and the Opium Wars of the mid-19th century between our two countries.  The poppy tradition only goes back to the First World War, best part of a century after those rather shameful trade wars.  But whilst writing this, I've just had a thought - is it poppy = opium?  That makes more sense.