North Korea may have just declared war on South Korea

[limitles]

If you don't think the US already has plans in place to keep that from happening, you drastically underestimate our abilities and foresight. You also drastically underestimate South Korea's ability to defend itself. When/If NK is ever a real threat, we will deal with them. They aren't, so we don't.

Actually read somewhere that in 1984 the USA had a plan in place to neutralize the entire airforce of north Korea in 2 days. I imagine they could do so even quicker today.

These days if your immediate neighbor has nuclear capabilities and an insane dictator with not much to lose you might be excused for being a bit nervous.