The European Comission is not the only one to blame, since it has limited power on its own. The European Council (of which VDL is also a member) is in large part responsible for delegating the Comission to fulfill various duties such as negotiations with the US, as well as instructing the Comission on the expected results.
That said, any time the European Comission is assigned to any task or receives any power from the Council - it overwhelmingly acts in the best interests of the US, not the EU.
The main problem we're dealing with is that many EU states and institutions are filled with American assets. The system seems fine on paper, but everything goes to shit as soon as several heads of state/government are aligned with our enemies.