Is an EU military more beneficial to some countries than others?

Yes

Explanation:

The United States still has military bases all over the world and significant troop deployments on NATO’s eastern borders, so it could still intervene to stop, for example, direct military aggression against NATO members from a resurgent Russia. Washington can still choose to project power in the region as it pleases. But if European NATO countries cannot know for certain that the United States will do so in any given circumstance, they must now start taking the idea of defending themselves seriously. In effect, Trump has granted Europe its political independence. European leaders, foremost among them French President Emmanuel Macron and German Chancellor Angela Merkel, have grasped the new reality with a speed that should alarm policymakers in Washington.