I'll go one step further. Britain shoud never have been involved in the Great War!
Looked at simply, shorn of emotional and ideological colouring, the entire history of Britain since 1066 CE (at least), screams one message: "Stay the Hell out of mainland Europe!" The Hundred Years War, the Napoleonic Wars, the great War, the Second World War, plus innumerable minor conflicts in between, should show that Britain has never had anything but trouble, expense and general misery from such interventions.
This was particluarly true in the 19th Century when a unified Germany rose out of the ashes of the Holy Roman Empire to challenge France for European hegemony. This is a rivalry which continues to this day and remains at the seething core of the EU. Britains' interests, especially after the Eilizabethan period, were overseas - they should have stayed there.
We would have lost, or surrendered, the Empire anyway. But without the European Wars, the transition from Empire to Commonwealth would have been more ordered. There might well have been less violence, less division, fewer wars and dictators, across the developing world had Britain not been impoverished and exhausted by unnecessary participation in two Franco-German conflicts.