Depending on who you ask, half of South Koreans would say US is being an unreliable ally, casually talking about actions that could start a war in Korea. If bombs start falling on Seoul, it would matter little to my family and friends who fired the first shot.

The common sentiment is "Shit, our allies and enemies are led by idiots. (Not to mention our own country, for the time being.) Let's hope nobody's crazy enough to do something stupid..."

They're all just showing off. I understand your concern, but South Korea is technically still at war with the North even if everybody only fires warning shots and plays propaganda over the border to annoy their neighbours.

Well my argument is that all US allies too should increase trade with Kim.

> So the US will never increase trade with NK to appease its sociopathic dictator

Well USA has very good trade relationship with China and Saudi both countries that would come second and third in terms of human rights abuses. In fact Saudi is a close ally.

It appears to me that USA wants a war and not to de-escalate the tensions and bring peace. All this eventually will come a a huge cost for South Koreans and US taxpayers.

When was the last time sanctions really worked ? India and Pakistan have very good nuclear arsenals and continue to build advance weapons despite all the threats and sanctions. Russia did not return the Crimea because of sanctions. Iran did not abandon its nuclear program because of sanctions.

The US is being pragmatic. China and the Saudis are countries you can do business with, not some wannabe bully threatening their US-allied neighbours and the USA with nukes. The last thing the USA wants in the Korean peninsula is war. They want to continue to do business as usual with South Korea, Japan and China without some pesky fatso dictator threatening regional stability with duct tape built nukes and ICBMs. But if it takes a few preemptive strikes to neuter Kim, they will gladly lend a hand.

South Korea itself had trade deals with its Northern neighbor until recently: https://en.wikipedia.org/wiki/Kaesong_Industrial_Region

Yup, until NK started testing nukes and making threats.