I think you are overestimating North Korea, not to be rude but you need to do a little more research before making some posts. During the first korean war the soviet union bankrolled and armed the DPRK army. The Soviets trained and equipped Kim Il Sungs Korean Peoples Army (KPA, the North Korean Army) and supplied weapons to Mao Zedongs Chinese Peoples Volunteer Army (CPVA). Soviet MiG-15 fighter pilots, radar operators, and anti-aircraft gunners were deployed to fend off the U.N forces. The North has a large force indeed but does not posses the industrial base for sustained war not to mention no longer having the USSR around to help. The South has dominance in the air (9th largest air force in the world) and is not too outnumbered in it's ground forces who have much better training, logistics and weapons. The souths navy has the Aegis fleet-defense system which is very advanced compared to the north. Numbers do count for something but I suggest you look up the military strength of Iraq and their numbers leading up to the first gulf war, look at how many armored soviet era pieces (similar to NK) were destroyed by better western systems which Korea has. In the initial days of the war the north would unload all artillery cannons causing many civilian deaths but you can only go so far with artillery. With American support/intelligence the ROK knows where these pieces are located and probably already have them zeroed in with their mobile rocket artillery and missiles. "The south just has US equip to defend themselves" This right here tells me how unfamiliar you are with ROK military forces and their capabilities. Stalemate at worst, ROK domination at best.