What leavers say
Brussels is determined to centralise control of defence. The EU – backed by such countries as Germany and Spain – wants to create a European army which would risk undermining Nato.
Pressure for closer military ties are set to intensify following the referendum. Meanwhile European judges are claiming jurisdiction over UK forces on active service.
The European Union Act of 2011 says British defence powers can only be handed to the bloc with the approval of MPs and a referendum
EU bureaucracy has tied up the Ministry of Defence in red tape, leading to delays in building Typhoon aircraft and new aircraft carriers.
The EU has proved inept in defence issues. It failed to cope with Yugoslavia’s disintegration in the 1990s and bungled its handling of the Ukraine crisis.
What remainers say
Annual defence spending would be cut by between £1bn and £1.5bn because of the economic hit from Brexit, with plans scrapped to build warships and jet fighters.
Talk of a European army is an alarmist “red herring” which has been promoted for years by Eurosceptics.
Some European politicians are drawn to the concept as a bulwark against Russian expansionist ambitions.
But Britain – although it supports military co-operation between member states – has no intention of signing up to it.
The British armed forces would never countenance any such move. Nor would the United States.
European Union member states are in charge of their defence policies and military spending.
But they can run joint operations under the EU banner: examples include operations in Macedonia, Mali, Congo and Bosnia.
The European Defence Agency, which is based in Brussels, coordinates such operations. It says it “is a key player on issues ranging from Iran’s nuclear programme and stabilising Somalia and the wider Horn of Africa to fighting global warming”.
EU treaties allow for “the progressive framing of a common defence policy that might lead to a common defence”.
They also say that such a move has to be agreed unanimously – in other words, the UK has a veto over any move towards “common defence”. (“Common defence” is not precisely defined).
The European Union Act of 2011 says British defence powers can only be handed to the bloc with the approval of MPs and a referendum.
However, the EU Commission President Jean-Claude Juncker has said: “A joint EU army would show the world that there would never again be a war between EU countries.
Such an army would also help us to form common foreign and security policies and allow Europe to take on responsibility in the world.”