IS were just copying what the North Vietnamese did in south Vietnam.
That defeated the USA!
However in the Middle East we have the Kurds and others who are hell bent on revenge!
You always have to remember in Nam, the bulk of the grunts were drafted.
swerving slightly off-topic, I can highly recommend The Tunnels of Cu Chi by Tom Mangold for bedtime reading.
There came into being a special breed of soldier - the "Tunnel Rat" who developed highly specialised skills for underground warfare. :guns:
shale, water and poor air's bad enough; punji stakes and booby traps would just ruin your day.
MARK