I don't speak much French, so I am unqualified to judge the merits of the argument going on at the French wiki now. But let me offer an opinion that may help guide those who do understand:
In the American legal system (and probably others), you can win or lose a case on its merits, but you can also lose by not following the rules of the system. This is called "procedural default", and is necessary to keep the system working: if a party refuses to show up for court, or complains to the wrong court, or doesn't respond properly to the court's questions, etc., then the court will not waste its time digging further into the issues of the case--it will simply declare that the uncooperative party loses. If someone wants a dispute resolved, it falls upon him to ensure that he treats the resolution system seriously and follows the process, otherwise there's no point in having a system at all. In extreme cases, if a litigant actively interferes with or subverts the process itself, casuing the court to waste its time and money, the party can even be sanctioned or charged with contempt of court.
When Wikipedia admins are called upon to resolve disputes, they should have the same powers. If it's something like a dispute over naming or content, a user who ignores legitimate questions posed to him, argues in the wrong place, and so on, should not be surprized when a sysop rules that his opponent's argument wins simply because his opponent behaved in a more civilized, productive manner. Likewise, there are some offenses that are so egregious as to merit sanctions: editing other people's quotes to misrepresent their opinions (but not just spelling mistakes and such), deliberate deception or dishonesty of other kinds, like lying about what one has said previously, or about what someone else has said.
I don't put mere hot-headedness into any of those categories: people get excited and say nasty things, and I don't have a problem with that as long as they keep the system working. But when they actively work to defeat the system, they need to lose, or the system stops working.
So, those admins who want to take some responsibility for the foreign wikis, do it. Don't be afraid to tell an uncooperative user that he is losing precisely because he refuses to cooperate. Block users, temporarily or permanently if necessary, if they actively work to subvert the system. If you need more technical assistance to exercise those powers, ask for it. Take control. Do what's necessary. We'll probably support you unless a dozen reasonable-sounding users give us good reasons not to.