Landmines are necessary to protect South Korea  The defence of South Korea from Communist aggression depends upon the thick belt of landmines that lines the demilitarized zone. Without it, North Korea’s million man army could easily cross into South Korea and take Seoul before defences could be organised. [1] South Korea is a key ally of the USA and to join in the ban on landmines would be to betray that ally. The failure of the Ottawa Convention to grant an exception for the Korean peninsula was the key reason for USA non-participation.  With regards to the tunnel network: North Korea would never be able to perform an invasion through a dozen half-finished tunnels just big enough for a man to pass though. Troops passing under the DMZ without any heavy equipment or armour would have to assemble in the open with no protection from RoK and US firepower and air support. The main force of any invasion would have to travel over ground.  [1] Marin, ‘Peacemakers Along the DMZ’, 2002