However, it is impossible to know for sure exactly how much of this kind of activity goes on, since these kinds of direct contacts, which provide first-hand information to both sides, are rather sensitive.
只是這種可以直接窺得兩岸第一手訊息的管道十分敏感，究竟美國智庫有多少類似的兩岸訓練或交流活動正在進行，外界很難得知。