The Second Korean war could start this weekend.
South Korea will fire artillery into waters controlled by South Korea but claimed by North Korea.
The North will probably strike the island again with artillery.
The South will probably bomb the artillery sights.
If this happens, it will be up to North Korea to decide if it wants to begin the Korean war again.
'North Korea sees South Korea's plans to conduct a live-fire artillery drill this weekend as "needlessly provocative," but the US insists it is normal and necessary. '