Reader Ted (ex-USMC) sent the following:

I'm ex-military having served in the US Marine Corps from 1968 t0 1972.In the military there is such a thing as an "unlawful" order which by its very nature service personnel are not obligated to follow. In fact, the argument could be made that they have and obligation not to follow such an order. I put this to the test in Viet Nam while having the Commandant of the the Marine Corps staring me in the face and "reading me the riot act". Fortunately for me, the Secretary of the Navy was standing next to him at the time and the Secretary of the Navy agreed with me. Had he not, I had already decided to see things through to the end and I intended to use as part of my defense that the order I had been given by my Captain was an unlawful order. There is a reasonable assumption that being forced to take these shots could result in a large part of our military not being able to carry out their mission due to serious complications or even death from these shots. Therefore, the order to do so is an unlawful order.