Another in our occasional series of comments that ought to be posts: Rob Farley discusses a Max Boot article in which Boot accuses Britain and Canada of "unilaterally disarming" on the grounds that Canada had the world's third largest navy in 1945. Farley, of course, gives Boot short shrift, but does point out that armies have got smaller throughout the world.
Only one problem, though, and that's that the example is bad. The British Army of 1930 was barely bigger than it is today. In fact, the British Army has almost always been the size it is now, excluding the world wars and the national service period. In 1930, for example, there were only two divisional headquarters. There are only two deployable division HQs now, and two more reserve formations.
In 1930, the forces deployed around the world by the British Empire were not large at all. Certainly, there were more than the current deployment, but not that many more. It was frequently observed, throughout the long 19th century, that the British empire got by with fewer soldiers than, say, Serbia.
For one thing, the empire depended quite heavily on locally recruited units, many of which were funded from local taxation. The Indian Army, for example, wasn't subsidised from London until its mechanisation in the mid-1930s. In a sense, British India was almost an independent state - at least, it often had its own foreign policy. Although one-third of the Indian Army's manpower was British, those officers and men were paid from the Indian budget.
The "white dominions" - Canada, Australia, New Zealand, South Africa - all had their own armed forces, although British politicians regularly moaned that they didn't spend enough on defence, over-relied on the Royal Navy, which was purely UK-funded, and were essentially free-riders. There are TYR points for anyone who notices the parallel with the US/European NATO arguments during the cold war.
Now, the Indian Army was a major security exporter, as it offered a pool of troops that were free, at least from London's point of view (the view from New Delhi was of course different). Hence, Indian troops were occasionally deployed anywhere in a space defined by Malta, Cape Town, Tientsin, and New Zealand.
Another important factor was that the British Army's infantry battalions stationed in the empire were effectively on barracks duty. Each of the regiments would have one of its battalions stationed in the UK and one overseas at any given moment, and they swapped every fourteen (!) years. The cost of maintaining a battalion abroad was significantly less than in the UK simply because of the price differential.
Now, everything in this picture transforms when you get to the big wars, when the Army erupts in size and concentrates in theatres of war. British units are combed out of the Indian army, as in 1914, or else Indian formations are deployed next to British ones, as in 1915 or 1941. And the dominions mobilise hugely, like the Cannucks building the world's third biggest navy.
There are currently about 10,000 British soldiers in Iraq and Afghanistan, but the respective cost of supporting them is much higher, even if you discount technological change, because both of these deployments are expeditionary ones far from any of the army's infrastructure.
In 1914, as the British army mobilised, a complex succession of shipping movements began around the world combing out the regular battalions on their 14-year deployments and rotating newly-mobilised territorials in to backfill them, not to mention Indian units out of India, and to pick up the first convoys of Australian, South African, and Canadian volunteers, as well as (later) the 1st Indian corps. But the killer detail here is that the regulars brought home made up first the 7th Division in time to get slaughtered at First Ypres, and then the 29th Division, the last of the regulars, in time for Gallipoli. That was it - two divisions, 14,000 men. Which isn't far off the current deployed total.
The argument from the Royal Canadian Navy is also rather poor. The Canadians achieved something incredible in going from essentially no navy to the third largest, but what Boot doesn't tell you is that this was a navy razor-specialised on one task, North Atlantic convoy escort. Just counting ships doesn't tell you that these were almost all corvettes and other ASW types, that and small escort carriers.