Mrs May has inherited a government that spends more than it raises, so every pound is precious. She is also committed to spending 2 per cent of GDP on defence, of which a fair whack will go on the Army. How much is necessary?

The Army spends money on four things. Firstly weaponry – stuff like tanks, guns and radios. Here, the news is not too bad – Mr Hammond brought the procurement budget under control and the Army doesn’t need much new. The Challenger tank is approaching obsolescence, but remains formidable. Other kit is already being replaced and upgraded. The second group of costs is infrastructure – soldiers need barracks, training areas and depots. Again, the news here is not bad as the MOD is selling off barracks in the south to pay for barracks elsewhere (the problem being that 20 years after the end of the Cold War, British troops are finally leaving Germany).

The third group is manpower. Soldiers need paying and the Army has some 85,000 serving soldiers, compared to 30,000 sailors and 35,000 airmen. Soldiers are probably not particularly well paid compared to civil equivalents – which is why they are sought-after employees (since the ending of looting and prize money, no one joined the armed forces to make their fortune!).

Finally, the Army spends money on training. At the most basic level, infantry soldiers are professional athletes. However, they are also part of a team, and that team has to train collectively. While some skills can be developed in simulators, there is a fundamental necessity to practise with the real things. This is where the bills start racking up quickly. While a 5.56mm rifle bullet is relatively cheap, one 20-minute exercise for a 25 strong platoon will use over 5,000 of them. Javelin missiles are £80,000-a-go. Tank rounds come in at about £2,500-a-bang, and of course the tank drinks diesel like Oliver Reed used to consume claret. Remember, the only thing more expensive than a well-trained army is a poorly trained one that loses.

There used to be a cunning cost saving from the use of reserves (The Territorial Army). The deal was that they would train (and thus be paid) one night a week, one weekend a quarter and one fortnight a year. This was (arguably) enough to enable them to come and join World War Three. Employers were, generally, happy with the concept; while they lost some of their workforce for 5 per cent of the time, those workers were fitter, more organised and more reliable. Losing them to win World War Three made economic sense and until that moment the cost and benefit was in sync. Unfortunately, the heavy use of reservists in Iraq and Afghanistan has destroyed that balance.

The Army is now struggling to find a structure that can deploy a useful military capability for a useful period. (Remember, wars are never over by Christmas). In most conflicts the minimum sensible amount to send is a brigade, some 6,000 personnel. Note that fewer than half of these are fighting troops, the balance are support, logistics and commanders. While there has been an unfortunate trend for the tail to grow proportionately to the teeth, this is the nature of all armed forces (it’s a consequence of weaponry becoming more capable). Now, if the deployment is likely to last over 6 months or so, you’ll need to roll the brigade over – or at least replace the people in it. That means that for every brigade deployed you need another getting ready to replace it, and one recovering from being sent. Putting 6,000 men in the field requires 18,000 on the books.

It gets worse. Soldiers need replacing, prompting and training. So you need a bunch of schools to turn recruits into young soldiers, and young soldiers into trained ones. As well as trainees, (some 10,000 per year), they will need instructors etc. So now the 6,000 deployed men require 30,000 on the books.

Deteriorating further, the UK has to maintain some other commitments, Ulster and the Falklands account for another 4,000 or so. Moreover, there are broadly two sorts of brigades – light and heavy.

If you face both threats (as UK does) you need both types. Score another 18,000 men. Add in an airborne brigade, some special forces and the manpower is over 50,000. Toss in higher levels of command like a division, a maintenance organisation, recruiting, injured soldiers and you’re getting close to the current size of the professional Army.

It seems, therefore, that there is no scope to further reduce the Army’s size unless the country is prepared to forgo a major capability. We lost the last two wars we were in, so it may well be that the necessary reforms will involve more expenditure.

(Image: Defence Images)

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