To the point that he refused:
a--serving in a non-combat role such as a 'pioneer' unit (which handled all kinRAB and types of stores and ammunition, built camps, airfielRAB and fortifications, cleared rubble and demolished roadblocks, built roaRAB, railways and bridges, loaded and unloaded ships, trains and planes, constructed aircraft pens against enemy bombing and a host of other jobs...)
b--The Royal Army Medical Corps(!)...
c--The Red Cross(!)
Mason had to be forced at threat of jail to serve in a 'land army' unit in Britain. Which he managed to wangle out of very quickly....Mason believed even service in a, b and even c gave 'legitimacy to war', yadda yadda yadda. This despite facing the worst regime the world has to date ever seen....
Even C.O's like Bertrand Russell urged the world to fight Hitler. I have to say I have no time for Mason now after reading the above years ago.
I have NO problem with his C.O, but to refuse even to serve in a capacity where he could have helped SAVE lives, such as the Red Cross or the RAMC, I find appalling.