You want a method for presenting whether or not we spend enough on defence? Here's a few ideas how to you get the "no" point across:
1. Make note of the manning of the Canadian Military post Korean War (1950-1953):
1953: 104,000
1957: 120,871
1967: 110,000
1970: 88,000
1980: 80,000
1999: 60,000
The Government constantly axed large portions of the Regular Force, by way of scraping Capital Warships (i.e. HMCS Bon Aventure), converting Regular Army Regiments to Reserve, and chopping the number of operation fighter squadrons in half. With all of these cuts went man power.
Army
At the height of it's decline, the Canadian Army (in the late 90's) was so short of manpower that of it's nine (9) Primary Infantry Battalions, only 6 were at or near full strength. The other 3 (2nd Battalion PPCLI, 1st Battlion R22e, and 1st Battalion RCR) were held in a 10/90 role; 10% regular force infanteers, 90% reserve infanteers, thereby making them utterly ineffective. The Army also did away with 81mm Mortars in all of its Infantry Battlions in 1997, thereby taking away close indirect support. The reason? Not enough men to crew mortar batteries. In addition to 81's, in 1998 the Army was forced to remove DFS Companys (Direct Fire Support) from all the Infantry Battalions. DFS Companys form the corps of battlefield support for the Infantry, comprising; mortars, assault pioneers, TOW anti-tank, and javelin anti-air systems. DFS Coys were axed once again due to a lack of manpower.
Navy
In the late 90's the Canadian Navy lost two (2) of it's 4 Iroquois Class Command and Control Air Defence Destroyers. HMCS Hurron and HMCS Athabaskan were "laid up", that is to be kept in unmaintained reserve. The culprit? Manpower shortages. There were simply not enough sailors in the Navy to crew all of our warships. Also in addition to the two Irqoquois Class, 3 of the 12 Kingston Class Maritime Coastal Defence Vessels (MCDVs) were laid up (2 in Esquimalt and 1 in Halifax).
Airforce
The Airforce was forced due to manpower shortages to reduce the number of Operation Tactical Fighter Squadrons (CF18 Hornets) from 9 to 4. As a result Tactical Squadrons were removed from CFS Comox B.C. and CFB Greenwood Nova Scotia. Therefore there are no fighter aircraft along either of Canada's coastlines. In the late 90's Canada had 32 CC-130 Hercules cargo aircraft (we still do). Of the 32 aircraft, only 17 were crewed (3 for air-to-air refueling, and the remainder for cargo operations). Manpower shortages once again.
2. Make note of outdated equipment:
Army
Leopard C2 Main Battle Tank: The Leopard entered service in 1980 as the Leopard Ce1, however was updated to the C2 in the late 90's. The upgrade package was simply a new turret with better targeting systems. The Leopard is still very dated, lacking modern stopping power with only a 105mm gun, and no ability to fire depleted uranium rounds. The Leopard is also slow, painfully slow. While it has a listed top speed of 65km, the new turrent and updated armor package force the Leopard to a crawl of around 50km/hr, while the Americans drive the M1A2 Abrams which has a top speed (which it can reach) of 72km/hr. The armor on a Leopard C2 cannot stop modern weapons and in some areas can be stopped by a simply RPG-7 which our enemies use in excess. Modern tanks are fitted with Cobham armor, a glazed ceramic that deadens impact.
LSVW: This light truck is a piece of junk. It was bought bargin basement in the 90's and simply put, does not do the job of an Army truck. It is slow (max road speed of 85km/hr), top heavy, and breaks down more than any other vehicle in the Canadian Army. This truck even requires a boost at times in +20 weather.
Navy
Iroquois Class Destroyers: Purchased in the 1970's (albeit refitted three times), they are simply past their prime. They require thousands of manpowers to keep them working, and the cost of new ships has been greatly outweighed by the cost of maintaining these old ones.
Victoria Class Submarines: Junk. Scrap bought from the Royal Navy in '98. Of the four currently in service, none, I say again none, are currently fit for service, all laid up in port. The Chicoutimi has caught fire (and killed one sailor), the Victoria had it's dive planes stick, and the Windsor flooded on a test dive. As Peter McKay put it, the Victoria Class are simply bargain basement vessels.
Airforce
CF-18 Hornets: When I was young, I saw the first CF-18 fly in Canada at CFB Cold Lake in 1982. The Hornet is as old as I am, 24. That is ancient by fighter aircraft standards. The CF-18, while still speedy, lacks the hardpoints for modern munitions, and has an inability to interface with American aircraft, our partner in the defence of North America. What's worse, is that the Government plans to keep the Hornet in service until 2017-2020!! That will make CF-18's 35-38 years old at the time!
CH-124 Seaking: The Seaking has been in service since 1960. Making it the oldest aircraft in service (47 years). The Seaking requires (at present) 12 hours of maintenance for every 1 hour it flies (this from an AVN Tech friend of mine posted at CFB Shearwater). The Seaking was a great chopper, but now it's a liability. Having crashed and been grounded at least five (5) times in the last 4 years. Our warships need onboard ASW Choppers, that work, not Seakings.
3. Amount of Equipment
Army
Leopard C2: Currently the Army has 66 Leopard C2s. If you overlook the obvious dated specs of the tank, 66 Leopards is far below the manning that 4 Armored Regiments require. That means that there is a National shortage of Main Battle Tanks in the Canadian Army. The Army needs at least 200 MBTs to meet it's minimal manning level. In contrast the U.S. Military has 8,367 M1 Abrams Main Battle Tanks.
RG-31 Armored Patrol Vehicle (APV): The APV was introduced to combat the threat of IEDs to troops in Afghanistan. It is a great vehicle, but frankly we do not have enough. With less than 50 APVs in service, there are simply not enough to protect all our patrols in Afghanistan. Keep in mind also that some must be kept in Canada for training purposes (I believe we have 12 in Gagetown).
Navy
The Navy as a whole. Currently the Canadian Navy has:
12 Halifax Class Guided Missile Frigates
4 Iroquois Class Command and Control Air Defence Destroyers
12 Kingston Class Maritime Coastal Defence Vessels
4 Victoria Class Patrol Submarines
2 Protectuer Class AORs.
With Canada having the worlds largest coastline, that tiny Navy is nothing. By contrast the Royal Navy (with a small coastline to defend) has 105 ships (90 surface action and 25 fleet auxiliary).
Airforce
CF-18 Hornet: Canada currently has 108 CF-18's (only 70 are crewed at present). With the worlds largest coastline, 70 Hornets, or even 108 for arguments sake are simply not enough to defend and monitor everything.
And for some comparison value; the U.S. Airforce has over 9,000 aircraft (that's not including the Army, Navy, or Marines aircraft either). The Canadian Airforce has less than 300 (mostly logistical).
There you go, just some ideas off the top of my head.