This event took place in 2005 and Hongkong Post issued this Postage Prepaid Postcard Series No. 15 to commemorate it.  There’s pre-printed, coloured postage (and valid for global airmail use) with a clear philatelic cancellation.  We were here in HK during this meeting.  People calling themselves “Korean Farmers” ensured that it was noisy and violent throughout.  Grade: 1