S2: Why did the US not know or understand the armor threat in Korea already?  Where was the national level intelligence apparatus to collect such information?  Why didn’t the US not equip the US Forces to deal with one of the biggest threats (armor) of the war?  Are we not doing the same thing today with respect to the CBRN threat?

I think the long and the short answer is that if the United States did not know the DPRK was possess of a significant number of T-34s then they had good reason to suspect the USSR would provide them at the very least. It was foreseen and done nothing about. The Truman administration did not equip the RoK army with such weapons or US garrisons in Japan because it did not want to be seen domestically or internationally as warmongering or starting an arms race. They intentionally weakened themselves to gain political support at home and in the vain hope that their enemy would respond in kind. They failed to understand the nature of their enemy, it does not desire to coexist, it does not attack in aggression because it is afraid of a threat but because capitalist democracies exist and must be destroyed. One signals through action not through disposition. Truman had forgotten the eternal truth learned on the island of Melos over a millennia ago, “The strong do what they can, the weak suffer what they must”. The only language enemies such as the DPRK understand is strength. While I can see some parallels today with Fehrenbach’s narrative, I believe that the North Korean focus on chemical and nuclear weapons is as much a signal of weakness as of strength. Their antiquated equipment from the late 60s cannot challenge the combined RoK-US forces on the field of maneuver. They are forced to use chem and nuclear as a way to gain advantage. If we are unprepared for chem attack, the DPRK is altogether more so. They lack the resources to operate in an environment of their own weapons. They can cause civilian causalities and delay and disrupt us, but they still cannot engage simultaneously with conventional forces. Thus they are reduced to threats and saber rattling to try and force concessions diplomatically. Words are weapons of the weak. For now, deterrence stands and has stood for over 65 years because we learned our lesson in 1950. It will continue to stand as long as “Fight Tonight” is a policy that the RoK and the United States have the physical and moral courage to uphold.