Was Somerville mentally affected by Mers-el-Kebir and the deaths of former French allies?
Short answerYes. The operation was personally repugnant to him and added to the accumulated burden that later weakened his effectiveness.
NotesMers-el-Kebir affected Somerville because killing sailors with whom he had recently served was deeply distasteful to him. Fighting a declared enemy drew on a different temperament from carrying out a coercive attack on former allies. Other British admirals might have executed the order with less hesitation, while Somerville did not possess that particular ruthlessness. This moral burden joined the illness, workload, and continuous operations already wearing him down without excusing his later mistakes.