AS the SNP revise proposed plans for self-government ahead of the 2023 independence referendum, special attention needs to be paid to defence.

Events over the past several years have challenged European unity and security, and shortcomings in the defence proposals featured in 2013’s Scotland’s Future appear a decade later more obvious and in need of redress.

Most glaring is the disconnect between ambitious security responsibilities and the meagre resources allotted to them. Fixing this problem will establish a strategic context for Scottish security, as well as indicate the spending Scotland should devote to defence, the armed forces it will need to build, and the benefits it might reap from the effort.

The old white paper claimed Nato membership as a cornerstone of Scottish national security but offered a defence budget short of Nato guidelines and forces smaller and less capable than those of similarly-sized alliance members.

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Scotland would “be committed to working in partnership and through alliances … such as Nato, OSCE [Organisation for Security and Co-operation in Europe] and the EU,” but would cap annual military expenditures at £2.5 billion – short of Nato’s required 2% of GDP.

Most alliance members are meeting this defence spending goal, including Norway and Denmark, as are Nato aspirants Sweden and Finland. Moreover, each of these countries’ combined active and ready reserve forces are about three times greater than the 20,000-strong Scottish defence establishment proposed in 2014.

Comparing Scotland to nearby nations of similar size, wealth, and security aims, the SNP’s old plans sought the security responsibilities of the Nordic states, but more like the defence spending and force development of non-Nato Ireland.

Reconciling strategic ambitions with defence commitments should start with ensuring policy aims are strong. If they are not, Scotland could reject Nato and other alliances, build forces for local security and international peacekeeping missions, and hope friendly countries secure Scottish interests better than unfriendly countries confront them. If these goals are still deemed worthy, however, then spending and forces need to be expanded.

Interestingly, Scotland’s Future estimated the country’s contribution to the UK defence budget to be £3.3bn – about 1.96% of Scotland’s estimated 2021 onshore GDP. Not only has this amount proven practically affordable over recent years, it also almost precisely meets Nato guidance and should be enough for Scotland to build forces capable of making immediate and significant contributions to the alliance.

The details of this larger Scottish defence establishment can be fleshed out over time, but it appears Scotland should be considering an armed service strength of around 60,000 combined active and reserve personnel – tripling the proposals put forward in 2014.

This would support a navy and air force capable of securing maritime and air approaches to the homeland, and effectively supporting Nato operations and a light, lethal, and deployable army of Nato-standard division size – as well as support elements to keep combat forces in fighting trim.

This greater defence effort would also advance other goals the 2013 proposals offered for the security apparatus, such as developing domestic industries, supporting a growing technology sector, securing “a strong conventional footprint in and around Scotland”, and “carry[ing] on the names, identities and traditions of Scotland’s regiments, including those lost in the defence re-organisation of 2006”.

Pursuing these other goals could yield economic benefits for Scottish enterprises, jobs for Scottish workers, and the development of national institutions. Shipbuilding, advanced technologies, co-assembly or production deals for military hardware and refurbishing bases and training areas would mean investment, advancement, and employment in all sectors involved.

Development of Rosyth’s facilities, a half-dozen air bases for three-plus air wings, and installations for larger ground forces would spread forces (and spending) around the country.

An army division plus contingents of separate, specialised combat units would create enough formations to resurrect a battalion of each of the historic Scottish regiments lost since the end of the Second World War.

The options an independent Scotland faces in national security planning are clear, as is which option returns the most on its investment.

The “have it both ways” option the SNP chose 10 years ago is the least workable, and the option that dramatically curtails international security commitments also weakens Nato and imperils Scotland’s and Europe’s security at a time of heightening threat.

The most reasonable option is to increase Scotland’s defence budget to about what it already has been spending, build larger and more capable forces, and secure membership and responsible participation in Nato. This option also goes farther toward achieving the economic rewards and other goals the old white paper promised would accompany an effective commitment to national defence.

The choice is up to the Scottish people. They are owed accurate, reasonable, and plainly offered analysis and proposals as they consider the practicalities of independence – a bold step the Government is encouraging them to take. Does Scotland stand ready?

Doug Humphries is a retired US Government defence analyst and Army officer now teaching at the Virginia Military Institute