The defence of the realm is the foremost responsibility of any government. The defence policy paper that will be debated in Glasgow this week is not only worrying, but potentially dangerous.

The first business of any defence policy is to recognise that the armed forces are to wage war in the name of our interests. We must be clear what these interests are. We can then be clear as to when we will deploy our armed forces into combat, what equipment they will need, the training they will require and the size and composition they must be. War is, after all, policy by other means – we must have clear policy goals to have a good defence policy.

Defending the Future is woefully unclear when it comes to what Britain’s interests are, and offers unsatisfactory foundations from which to construct our defence policy. There is no consideration that as an island we are highly vulnerable to disruption of global sea lanes by hostile actors. It does not ask what Britain’s commercial or political interests may be in different areas around the world. What is considered is that we’re not very keen on the Americans (who have the capacity to do lots overseas) but we are keen on the Europeans (who don’t). The paper is further muddied by apparently wanting the UK to continue to become involved in humanitarian interventions. Barring a radical shift in the internal politics of most European states, these are very likely to be outside of Europe – which will mean we need to either rely on the Americans to do all the hard work, or will have to retain sufficient capacity to send a meaningful presence to such a war.

This muddle over interests feeds into terrible recommendations when it comes to equipment procurement. The paper goes from stating “the UK cannot aspire to full-spectrum capabilities that would permit unilateral action around the globe” to arguing that “the UK should maintain a credible contribution to Expeditionary Forces, including carriers, land- and sea-based airpower and land forces rapidly deployable by sea or air.” Which is it to be?

The mess over procurement becomes almost farcical when it comes to nuclear weapons. Rather than making a convincing argument to disarm or to replace Trident, the paper settles on the dangerous idea of a part-time deterrent based on useless multi-role submarines. On the first point, any deployment of a UK submarine capable of deploying nuclear weapons during a crisis will escalate that crisis, because the boat will be treated as a live nuclear threat by our opponents. On the second, as cruise missiles are too vulnerable a platform to base our deterrent around, any multi-role submarine would have to carry submarine-launched ballistic missiles similar to Trident. This would transform our submarine fleet into one giant escalatory force – every boat deployment would risk increasing international tensions.

To its credit, the paper does a fine job of discussing the welfare of the members of the armed forces. This is poor compensation for its failure to deliver what must be its primary task – a clear articulation of British interests, and therefore a strategic vision for the country from which we can build procurement decisions and guide the use of force in years to come; or our reaction to it. Without these things, this defence paper represents an embarrassment to us as a party. We should refer it to the Federal Policy Committee to give us the time to make it worth the name.

* Tim Oliver is a party member in Leeds, who has recently submitted a PhD on British foreign policy at the University of Hull.