Let us assume the PM secures all his negotiating objectives. There will be huffing and puffing over the fourth, the 4 year ban in welfare payments to EU migrants, but doubtless there will be some bridge, some fudge that claims symmetry between UK benefit recipients and those from the rest of the EU around a four year delay. The trouble is, without Treaty change there are no guarantees, no change to the underlying UK/EU relationship, no protection against future penalties and policies that the UK does not like.
Any deal depends on the view of the European Court of Justice anyway. They could overturn the apparent success in a future case. Any part of our welfare system, reformed by the deal, can be found to be against EU rules, or can be altered by future EU rule changes that we might not be able to block.
Were the UK to vote to stay in the rest of the EU will claim we have been given very special treatment and will then wish to reverse as many of the concessions and special deals we enjoy as they can. There is continuous pressure to get us to drop what remains of our cash rebate. The UK government regularly gives into pressure to transfer more criminal justice powers to the EU. Part of Mr Cameron’s deal is to increase EU powers in business regulation and services. The Germans always make clear that they see the Euro as a necessary part of the single market. Most EU countries want the UK to be fully part of the common borders policy.
If the UK is foolish enough to vote stay it needs to understand what it is staying in. It is an emerging state called the EU, with the full range of state powers. It is a wild ride to political Union.
Mr Caneron’s renegotiation also shows how it is impossible to combine national democracy with EU sovereignty. If after every election in a member state that state needs treaty or policy change then the EU becomes unworkable. If instead every country accepts it cannot change any law or policy from the EU by a General election it us no longer a national democracy.