The 1880's boardgame Invasion included the channel tunnel as an optional rule for experienced players, adding another attack vector for the player trying to inv

The 1880's boardgame Invasion included the channel tunnel as an optional rule for experienced players, adding another attack vector for the player trying to invade South-West England. As I understand it part of the reason for creating the game was to show how dangerous it would be to have the tunnel. It fits in time with the examples in the article of worries about the tunnel's military use? https://boardgamegeek.com/boardgame/26597/invasion https://boardgamegeek.com/boardgame/26597/invasion https://boardgamegeek.com/image/3510336/invasion https://boardgamegeek.com/image/3510336/invasion