The Rule of Law
A Directive is not automatically national law, it has to be minted out in national laws by the appropriate legislature in order for it to take effect in any member state, individually. Still, most member states have signed the membership treaties fully, in a way that they can take precedence over national law by way of the judiciary. This creates an unclear legal status by introducing the EU Court as a further route of appellation so that the high court of a member state is not necessarily the highest and final decision point, even for legislation that is only for the member state itself and involves only citizens of that same member state.
This very basic workings of EU is in itself contradictionary to the principle of subsidiarity. It has to be stated once and for all that national law has prevalence over EU law in matters that only concern citizens of the member state in question.
In essence, the subsidiarity principle is just a patch to cover the real problem, not a solution to it. The underlying problem is that EU is hegemonous, it is not limited by treaty to the actual problems it set out to solve.
EU should adopt, in stead of the subsidiarity principle, a concise definition of the areas of jurisdiction. First of all, EU should cover far less areas of policy and jurisdiction. Second, the current restrictions should be respected in detail so as to avoid any expansion by bureaucratic forces rather than by political decision.
In order for this to happen, it is not only necessary with a tightening of the treaties and the way they are administered by the Commission. The democratic reach of EU should be much strengthened, mainly by conceding most major decisions to popular vote rather than the Commission and the Council of Ministers.
Im this process, the Parliament is somewhat sidelined, but the fact is - it is already sidelined and thus it must be cut down to a reasonable size. In the USA, there are 435 voting members of Congress and the Senate has 100, in total 535 members to govern a much larger budget than that of EU, In comparison, the EU Parliament has 705 members. The EU budget is around 186 billion Euro annually, whereas the US federal budget is 6.3 trillion USD equal to 5.8 trillion Euro. The counter argument is of course that the EU population is bigger, around 448 million people, compared to USA with 333 million inhabitants. Number of voters per representative elected politcian is about the same, yet is still stands out to the extreme, because the budget is so much smaller and the reach of the legislation is much wider than it needs to be in real life.
The EU court of top laws is constantly expanding reach in all areas where the Parliament has left vagueness in laws that allows for legal interpretation. The extent of this is totally unacceptable in a state or union with rule of law. The laws are decided by elected politicians that can be held accountable for their decisions, not by judges that cannot be unseated by the people. Can EU court judges be unseated at all? with some kind of legal process similar to what the US calls impeachment.