
In a nutshell here were some reasons for / against Canada maintaining a military:
Some arguments for:
Being able to defend territory is a critical component of a nation state, and cannot be ignored
Armed conflict is always a possibility, and Canada should always be prepared
It is part of Canada's treaty obligations to the USA and NATO; if we don't pull our weight it will have a negative impact
Canada has valuable land / resources that may come under increasing threat the easier it is to access (especially as the North opens up due to climate change)
Canada should not have to rely on the US for protection
Canada still makes important contributions to NATO / peacekeeping missions
Canada's military does more than just fight - peacekeeping, humanitarian missions, search and rescue, snowplowing (in Toronto) etc
If Canada dissolves its military it will give up sovereignty to the US/ Russia, China etc.
Although Canada's military is relatively small, it is well trained
If Canada eliminates its military it will lose valuable skills which, if needed later, will take time to replace.
Canada is a military nation with a proud history of taking a stand when necessary (e.g. ww2)
The Canadian military still represents a fairly sizeable chunk of the workforce and the economy (~1% GDP)
Some arguments against:
Barring nuclear deterrence (which is an options most Canadians are against), due to its geography (2nd largest landmass, largest in overall coast) and small population (which is concentrated in the US border) Canada is practically indefensible. The only countries which would conceivably invade Canada (Russia, USA, China etc) are also far greater than Canada in terms of population and military strength, making Canada's military ability a moot point. No matter how much money was spent Canada would be swept away in a conflict.
That being said, it is highly unlikely that any country would actually invade Canada - the US has no reason to, and they would prevent any attempts by China and Russia to establish a military presence on North American soil
Canada's military is obsolete in design - it is meant to maintain a small standing force that can train recruits in a major conflict. However, if there was a major conflict in the 21st century big enough to require a mobilization, it would likely be over (due to tech / WMDs etc) before mobilization could even begin.
While Canada's military is well trained, most of its equipment is horribly obsolete. Replacing that equipment would require a massive commitment and funding, far more than the public would be willing to tolerate.
The biggest threat to Canada is terrorism and crime, not foreign invasion. The money spent on the military would be far better spent on border patrol, coast guard, security services, spy agencies, policing etc
As for other functions, again funding would be better spent on actual organizations dedicated to search and rescue, humanitarian aid, snowplowing etc. than having the military do it
Canada's role in NATO is relatively insignificant; Canada no longer has an meaningful impact on modern military affairs
Canadians are generally against warfare in the 21st century, and do not see why Canada should be getting involved
Canada might have a bigger impact in the world by becoming the first G20 nation to completely demobilize than by continuing to go on NATO missions
Funding could also be redirected towards social services and reducing poverty - again, something that is having a far bigger negative impact on Canada today than the threat of foreign invasion
Jobs lost via eliminating the military can be offset by retraining members in other fields (such as navy personal being redeployed as coast guard, airforce as search and resource etc)
Canada would have a greater impact on the world stage by specialising in humanitarian aid - there are already plenty of much more powerful countries that have the ability to blow things up far better than Canada can.
Canada is a post nation state, and thus does not need a military as we conventionally view it.
Thoughts?