I Blame Communism
Banned
It was a convenient excuse, true, but it was good one- they actually *were* obligated by treaty to declare war on Germany. Which is why *any* French attack on Belgium (or a French ultimatum that Belgium bows to, for that matter), as unlikely as that is, is a problem. Britain might well remain a French-supporting neutral, simply because the alternative may well be that they end up in a post-War world where no-one trusts Britain will place any weight on treaties made.
As for French hegemony not being an issue, not as much of an issue, but France in control of the Channel Ports were no more desireable than Germany in control, nor were a Germany broken desireable.
Good point about the treaties. However it wasn't the 18th century. We'd moved passed Channel Ports paranoia as we were fully confident in our own naval strength: we were looking at the capacity to dominate the continent. Once unfettered by competition with other European Great Powers, a power was a huge threat to us. Even in the 17th Century, I think, this more sophisticated policy was only outwardly amifesting itself in staunch defence of Belgium for logistical reasons (in those days no fleet of any size could guarantee to stop an invading armada based inAntwerp because of wind).