The explicit support for a full-blown common defence policy is part of the strategy, laid out by Paddy Ashdown at his party's seminar in Oxford last week, to give the Liberal Democrats a clear policy identity for the general election. It is unlikely to be matched by Labour under Tony Blair.
It will be welcomed by senior pro-European members of Mr Ashdown's parliamentary team, who criticised the party's European campaign for being too timid over the abandonment of Britain's veto. The paper makes it clear that Britain could withhold the use of its forces outside the Nato area.
The roles of the forces allocated to the former Soviet threat, including the RAF in Germany, the Eurofighter 2000, and the Royal Navy in the north Atlantic, need to be reassessed, the paper says. As long as the quality and technological edge of British troops can be maintained it may be possible to secure further reductions in forces for a collective defence role.
The document would harden the commitment to nuclear defence, replacing a commitment to maintain nuclear weapons 'for the time being' with a commitment to do so 'while other states possess nuclear weapons'.
The party would deploy the four Trident submarines, with a minimum number of nuclear warheads, no greater and possibly fewer, than deployed on Polaris. They call for tougher curbs on the use of nuclear weapons, like those for chemical and biological weapons, and for Britain to renounce the use of nuclear weapons except in response to a nuclear threat and only against military targets.