Wow.First, at that point the French were not “allied soldiers” (sailors). They were Vichy whose government had made its deals with the Nazis. Let’s get that straight, shall we? Second, the French were given a non-combat deal to remove the fleet to other far away anchorages where the Germans could not get to them. The French fleet was not obliged to join the British fleet. The French refused. Third, kindly recall that the official French position at the time was that joining Great Britain in the fight against the Germans was tantamount to “fusion with a corpse” - while remaining with the Vichy government wasn’t? When all else failed, the British opened fire.
I don’t blame them. It was awful, horrible and stomach churning, but it had to be done.