Who started the war in 1950? It wasnt really NK.
The blame sits squarely with the US and Russia

The roots of the war are in the partition

After WW2 the US and USSR occupied the country, with the boundary between their zones of control along the 38th parallel. Negotiations failed to lead to an independent, unified Korea. 

They then rushed elections in the South only creating South Korea... a made up country mpt reflecting the will of all the people of Korea

So NK was established as well.. another non-country.
 The US supported the South, the USSR supported the North, and both claimed it all

Who fired the first shot is irrelevant... There should not have been 2 countries

This was the state of play all over the world after WW2
- Israel - Palestine partition
- India - Pakistan
- Vietnam - The only one that had a 'happy' ending

The super powers inserting themselves where they werent wanted  - they caused the war