The historical track record of the largest economy being
overtaken by another is not good. Sometimes it’s
violent. (For example, Germany and the UK in 1914.
To give WWI as an example of the consequences of GDP league tables seems like a bad reach to make the event sound apocalyptically important when it doesn't represent any radical change in balance of power at all.
As I understand it, the Kaiser's geopolitical motive was to avoid being dominated by the Dual Entente given Russia's growing strength. He expected GB to stay neutral given it was generally more friendly to Germany than Russia and was fairly isolated from European mainland issues given its interests in the colonies.
In any case, why compare UK GDP and not British Empire GDP which at that time would have dwarfed Germany?
The central question of the start of WWI was who gets to pick over the bones of the ottoman empire and to a lesser extent the bones of the austrian empire. Several very big players decided "it'll be me, and I'll fight everyone else for my share".
As I understand it, the Kaiser's geopolitical motive was to avoid being dominated by the Dual Entente given Russia's growing strength. He expected GB to stay neutral given it was generally more friendly to Germany than Russia and was fairly isolated from European mainland issues given its interests in the colonies.
In any case, why compare UK GDP and not British Empire GDP which at that time would have dwarfed Germany?