At the highest level, strategic direction is provided by senior figures within the UK government. Speeches and interviews given, as well as newspaper and journal articles written by prime ministers, chancellors of the exchequer, foreign and defence secretaries, provide insight and guidance on how the incumbent government is approaching its defence obligations. More recently, with the convergence of defence and security through the articulation of a strategy for national security, this list has grown to include other ministers, for example the home secretary and the Cabinet secretary. In addition, there are a number of non-elected officials who also write and speak on defence and security matters in an official capacity, the most notable being the National Security Advisor (NSA), the Chief of the Defence Staff (CDS) and the service chiefs, as well as the permanent secretaries to the ministries served by the politicians listed above. What flows from this verbal and written direction is defence and security policy, which, in simple terms, is what the government chooses to do, or not do, about a particular defence-and/or security-related issue or problem. The government has a generic approach to the formulation of policy; however, there are peculiarities specific to departments, including those responsible for defence and security. An obvious example of this is the defence review process.

Military capability is a term that has only recently been added to the UK defence lexicon. In 1997, the newly elected Labour government introduced the Smart Procurement Initiative (SPI) intended to deliver equipment ‘faster, cheaper and better’ (Taylor, 2003, p 7). This initiative was a significant theme in the 1998 SDR and was subsequently re-launched as ‘smart acquisition’ in October 2000. The currency of smart acquisition was military capability, defined as ‘an operational outcome or effect that users of equipment need to achieve’ (MoD, 2002, p 51). Since then, the process for the acquisition of military capability has developed significantly and is now cohered through a formal list of Defence Lines of Development (DLOD), which were endorsed by the defence management board in 2005 (MoD, 2005b, p 1). The 2015 version of the MoD’s operating model defined military capability as ‘the combination of equipment, trained personnel and support that gives the armed forces the capacity to achieve the tasks they are given’ (MoD, 2015b, p 8).