Wars are not obsolete. They have a direct and distinct purpose. I think the military is being sold short and not being given the full support they deserve. Under war, the US would dominate A'stan, make it friendly, then return it back to itself as a sovereign nation. Under the terms we have now, the soldiers are expected to fit a political mold of fighting. A wide mold for now, but a politically driven one. Viet Nam, anyone? I want the military to be told "Go get 'em". Not "Go get 'em, and clear everything with us, and, oh yeah, we'll be sending you our list of priorities." Under war, captured men are POWs. No war, they can be anything the enemy desires, including "terrorists", as the NVA would call us. War means the military has command of their actions. No war means the politicians retain full control, even if they give the military some slack. There are more things to war. Maybe after Korea, this country has forgotten what war means. "Do it if it feels good!"
The last declared war was WWII
Of course it's just my opinion, but wars certainly are obsolete as measured by conflicts and deaths and the lack of declared wars. Which is a pretty fair assessment.