The current U.S. administration has totally detuned policy making in Europe. Not that there have never been misunderstandings between the European Union and the U.S., but nothing like Donald Trump's inappropriate diatribes against European policies has ever taken place. Trump's totally unpredictable and insulting tweets have created a deep sense of frustration and unease among European leaders. That translates sometimes into reactive and blunt rebuffs. That was practically the case with the declaration made by French President Emmanuel Macron when he said that Europe needed a proper army to protect itself against Russia, China and perhaps the U.S.
This is the first time since the end of World War I that an important European head of state publicly acknowledged that the U.S. may turn into an enemy. Such a declaration would never have seen the light of day if there were an acceptable, intelligent and balanced presidency in the U.S. Alas, the world is watching Donald Trump demolish all the delicate balance and good manners in international relations. He has been more disruptive than a bull in a china shop, and nothing shows that his ardor in being ignorant, stubborn and unpredictable is going to vanish any time soon.
Still, Trump's insulting declarations have brought a real issue into the agenda: The European defense organization. Attempts to establish a purely European defense system alongside or parallel to NATO have been numerous. The best integrative attempt was made in 1950, through the Plan Pleven, to establish the European Defense Community. A supranational system was envisaged, including a totally integrated joint army and military-industrial infrastructure, obviously with a "political union." The attempt was largely motivated by the fear of seeing Germany rearm; the joint army would have been an instrument to control German military forces, diluted in a European joint command.
Even in 1952 the idea did not work, sabotaged by the French themselves, by refusing to endorse the treaty already signed by all European Coal and Steel Community (ECSC) countries except Italy. It is worth underlining that Rene Pleven, the architect of the project and twice Prime Minister of France during the Fourth Republic, was a staunch Atlanticist. His attempt to form a supranational European army chiefly aimed at establishing a strong link between the U.S. Armed Forces and his European army-to-be. Close collaborator and admirer of De Gaulle, he will nevertheless strongly criticize the latter's move to take France away from NATO in 1966.
Since then a variety of bilateral or EU-framed attempts have been made to ensure a modicum of cooperation in defense and security issues. From the West EU to the Common Defense and Security Policy pillar of the Maastricht Treaty, many institutional structures were established. None of them worked or works properly. This is due to a number of facts: First, there is NATO, which remains by far the most integrated and efficient military structure ever. NATO is dominated by the immense military might and technology of the U.S., which largely helped the EU countries to save on their military spending for decades. The "free riders" within NATO also preoccupied President Barack Obama, he was talking about member states who were wealthy but who do not wish to make further military investments.
That takes us to the second fact: Nobody in the EU is keen to spend more money and increase the military budget. That might take different forms, as Sophia Besch wrote in the Center for European Reform (CER) back in 2016. Dutch-German cooperation was established – the two countries today are effectively sharing soldiers, as well as tanks and other capabilities. But the Dutch-German integration was driven primarily by economics; the Netherlands scrapped its armor in the face of budgetary pressures and sought to offset the impact of these cuts by forging a partnership that allows Dutch forces to train with German tanks.The third issue is the deep differences between military traditions, training and defense cultures. In most of the EU countries, national security remains a national sovereignty issue and has to remain so.
The fourth issue is the divide between eastern and western European countries pertaining to the role of the U.S. No eastern European country trusts a purely European (and virtual) defense structure against the Russian military. For them, the U.S. remains the only viable guarantee for their security.
Finally, yet importantly, there are EU countries that insist on their neutrality; Ireland, for example, has obtained a whole protocol before signing the Lisbon Treaty, stipulating that such deepening of integration would not lead to the creation of a European army.
In view of all these developments, it would not be realistic to see a purely European defense force emerging any soon, but obviously, there shall be more money spent and better cooperation sought among all European countries for military purposes in the near future.