Frequent mention has been made of a long standing British policy to prevent any one european power gaining hegemony on the continent but one should remember that Britain remained neutral in the war of 1870.
Britain's role as guarantor of Belgium's neutrality was never called upon. Prussia, and Germany in general, had long been seen as allied to Britain in controlling French expansion and France had recently been seen to threaten Britain (hence the 'Volunteer' movement.)
Over forty years later it is Germany who is making the threatening noises and France as a friendly power. If Belgium was not attacked by Germany I see Britain as remaining neutral but supporting France with material aid sales and relieving the French navy from extraneous support to allow it to keep it's trade going and blockade Germany. Somewhat analogous to the USA in the first half of WW2.
Britain's role as guarantor of Belgium's neutrality was never called upon. Prussia, and Germany in general, had long been seen as allied to Britain in controlling French expansion and France had recently been seen to threaten Britain (hence the 'Volunteer' movement.)
Over forty years later it is Germany who is making the threatening noises and France as a friendly power. If Belgium was not attacked by Germany I see Britain as remaining neutral but supporting France with material aid sales and relieving the French navy from extraneous support to allow it to keep it's trade going and blockade Germany. Somewhat analogous to the USA in the first half of WW2.