Army Trains with Flame Throwers

Sam's 31st Engineers Assault squad demonstrates a tactical operation. Initially, they use a Bangalore torpedo to clear enemy barbed wire, followed by an assault on a pill box using flamethrowers. The flamethrowers force the defenders into cover, allowing for a final TNT attack to complete the mission.

What role have flamethrowers played in the context of this military operation?

What defensive strategy did the pillbox defenders adopt when faced with the flamethrowers?