What those campaigning to leave the EU seem not to understand is that British sovereignty has not been lost. Signing a treaty is an agreement between states to do certain things. It can be repudiated, though this is rare. It is up to the individual states to do what the treaty says. The UK has not signed up to as much as other EU states, but has done what it has agreed to. Two apparently contrary examples show this. The first is on controlling our borders, the second about trade negotiations.
The UK did not sign the Schengen agreement, and opted out of it in the 1999 Amsterdam Treaty. The UK has therefore at all times been in full control of its borders. The fact that its governments have not spent enough on border control has nothing to do with the EU. It is the UK’s fault if its border staff cannot access lists of undesirable aliens and lets them in. It is the UK’s fault if it does not check who is leaving the country, and find out who is overstaying their visa. The Tories have chosen to set net migration targets, which cannot be measured, never mind met, on current staffing levels. If we knew who was leaving, we would know how long people coming to the UK stay.
On trade, all the member states have agreed that EU trade negotiations shall be conducted by a single person, the Trade Commissioner. This does not mean that the Trade Commissioner can do what she likes. She receives a negotiating brief with input from the Council of Ministers, the 28 heads of government. The brief also has input from the elected European Parliament. The European Parliament can refuse to ratify a draft treaty. The 2009 Lisbon Treaty further requires much greater input from national parliaments. The Transatlantic Trade and Investment Partnership (TTIP) negotiations with the USA have generated a lot of concern in many EU member states including the UK. In particular, people worry that the proposed arbitration arrangements may allow big US companies to put pressure on governments. The idea of companies avoiding having to settle disputes in the courts is not liked. France and Germany are so concerned that they have issued a joint statement that they want TTIP to be recognised as a ‘mixed’ agreement. This means it must be ratified by all 28 national parliaments and not just the European parliament. At the beginning of May, the relevant French minister was reported as saying he believed the talks had come to a halt. This shows that working together in Europe increases the public’s clout in negotiating with the world’s most powerful nation.