You're missing the forest for the trees.
The scene between Colonel Jessup, Lt Jg Kaffee, and Lance Corporal Dawson and PFC Downey is about the nature of contradictory duties.
Everyone in that scene has a sworn duty to the United States as active duty military.
However, their duties sometimes conflict with each other (Jessup and Kaffee), and are even sometimes self-conflicting (Dawson and Downey).
Bad doesn't always come with a sticker labeling itself, and there's trauma inflicted even in peacetime in the maintenance of military strength (in broken bodies, training deaths, and emotional trauma).
To hold ones nose and pretend there isn't constant violence, even absent declared war, being perpetrated to militarily protect the US and Europe is to be ignorant, willfully or otherwise, of the foundation peace is built on.
Jessup is a tale of the distinction between the reality of war and the higher ideals and laws of war.