and this will result in huge cost and huge strategic set backs in other parts of the world.
they know they can't leave south China sea.
they can't leave north Korea.
they won't allow
anyone to threaten their trade routes.
And not to forget that defence is easy than attacking.
important part of the whole scenario is Russia will not miss the chance to revenge collapse of soviet union.
Iran will not hesitate to help us for the fear of being the next victim.
China won't allow it like it is not leaving north Korea alone and the reason is that china won't allow itself to be encircled by US. a small war in south china sea or any hostility and US on Pakistan soil will ruin china dream of becoming the super power.
The USA military has the ability to fight Pakistan and North Korea at the same time
If North Korea starts a war there will be little consideration to collateral damage. it will be re-run of what the Allies did during WW 2 on Germany & Japan.