The biggest incentive for them to work together rather than pushing for reforms specific to an individual country is to match the power of the US government on

The biggest incentive for them to work together rather than pushing for reforms specific to an individual country is to match the power of the US government on the world stage. This was one of the main reasons for the creation of the EU to begin with, to compete with the US. As powerful as a strong economic country like Germany can become, they still pale in comparison in size to the US. Working together cohesively with other EU nations could create a superpower to rival China, USA, Japan, etc.