I would say yes. If you were the Brits, could you have staked your naval supremacy in the Med (and therefore your national surival), on the willingness of citizens of a defeated, demoralized and occupied country to resist all the pressure the Nazis could bring and keep their fleet neutral? De Gaulle (and those French naval officers who subsequently DID join the Allies, despite Mers El Kebir) were the exception, rather than the rule.
An interesting sidelight of the whole tragic incident was the effect on world opinion regarding Britain's will to survive. According to "The Duel", a book about the struggle between Churchill and Hitler during the period between the fall of France and the start of the Battle of Britain, the British action at Mers El Kebir went a long way to convincing the Roosevelt Administration that the British really meant to fight and were therefore worth assisting.
Altogether, a VERY sad event, which I gather still exercises some influence on Franco-British relations.
