Ernie Regehr says No

The U.S. ground-based mid-course missile defence system, known as GMD, is deployed to protect the U.S., and potentially all of North America, from nuclear-armed intercontinental ballistic missiles—it’s the system Canada is considering joining. 

The first thing to understand about GMD, however, is that it’s not intended for, or capable of, defending against Russian and Chinese ballistic missile attacks—a limitation confirmed in the 2022 U.S. National Defense Strategy. 

Indeed, GMD also offers no defence against Russian and Chinese cruise and hypersonic missiles—both are out of reach of GMD interceptors designed to stop incoming warheads in outer space. GMD’s 40 interceptors in Alaska, plus four in California, are focused only on blocking a limited attack from rogue nations (namely, North Korea). 

It turns out GMD addresses fewer than three per cent of nuclear warheads worldwide aimed at North America. And defending against even that tiny fraction of the threat is not a sure thing. The Pentagon makes only this modest claim for GMD: it can “help mitigate damage to the homeland and help protect the US population.” Certain protection is not possible. 

In any attack, some nuclear warheads would likely get through the defences.

In short, GMD helps to drive a new and destabilizing arms race. 

GMD also undermines arms control. Without strict controls on missile defence to bolster U.S. assurances that GMD is not directed at Russia’s nuclear deterrent forces, negotiating a new pact that goes beyond the current U.S./Russia New START Treaty would be difficult. 

Russia and China are both concerned that the current GMD infrastructure could, in the future event of technological breakthroughs or changes in U.S. policy, facilitate a sudden surge in missile defences that could undermine their own ballistic missile deterrents. Hence, the Russian and Chinese focus on developing long-range cruise missiles and hypersonic systems against which GMD interceptors are powerless. In short, GMD helps to drive a new and destabilizing arms race.  

When considering GMD, some Canadian military analysts focus on the program’s operational connection to Norad. This U.S.-Canada joint command is responsible for, among other roles, early warning of a missile attack, relying on U.S. hardware, but involving Canadian personnel. U.S. Northern Command, however, is responsible for GMD interception operations, and Canadian personnel are excluded. Joining GMD, they argue, would remove this command structure complication, but Norad’s primary missions are joint air defence and maritime surveillance, the command structures for which are clear. 

GMD offers little protection from global nuclear threats, exacerbates a technology-driven arms race and undermines arms control—all of which counsels against Canada joining it. Because there is no reliable defence, responding to nuclear threats has come down to preventing attack through deterrence. 

Given that the threat of mutually assured annihilation can never be a satisfactory foundation for long-term security, the only safe, viable solution to the existential nuclear threat is urgent arms control and disarmament. 

James Fergusson says yes

Ground-based missile defence is a reality. And Canada has little, if any, access to information about the capabilities, value and utility of GMD, particularly relative to the defence of the country and the continent in co-operation with the United States. While Canada, via Norad, provides warning of a ballistic missile attack, the “defeat” side falls solely to unilateral U.S. decisions.

The current American continental GMD system is under U.S. Northern Command. While it is twinned with Norad, it excludes Canadian personnel, and thus Canada, from any access to U.S. operational GMD plans. Whether the U.S. would defend Canadian cities from a limited ballistic missile attack emanating from North Korea is unknown, as are the conditions under which it might do so. This is a U.S.-only decision, and the Americans have made it clear that unless Canada agrees to participate, it doesn’t have the right to know. 

This alone dictates that Canada should participate to gain some access to U.S. thinking and plans, regardless of how the subsequent detailed negotiations turn out.

Failure to participate in GMD will likely have significant repercussions for Canada.

Beyond this fundamental logic for participating, two recent developments further reinforce why it’s pressing to avoid the marginalization of Canada and Norad in the North American defence relationship. 

First, if the U.S. builds a new GMD site in the U.S. northeast to defend against future threats from the east, Canadian territory will become essential to its operational effectiveness. Specifically, this will require, at minimum, a forward tracking and battle-damage assessment radar to support the interceptor site. Failure to participate in GMD will likely have significant repercussions for Canada by generating perceptions that the country is a liability in continental defence.

Second, given the new threats posed by advanced long-range cruise and hypersonic missiles and the current modernization of Norad and continental defence, the U.S. is moving rapidly to integrate its air and missile defence capabilities. In other words, the longstanding separation of air and missile defence is ending. Norad is in the missile defence world, and failure to respond will marginalize it, ceding Canada’s defence to the U.S.

Not joining the GMD would suggest the Canadian government is not interested in defending Canadian cities from a limited nuclear ballistic or hypersonic missile attack. And there is a misguided belief that Canada’s adversaries would never attack the country and that protecting Canada is a U.S. responsibility. 

While the costs to meet Canada’s goal of assigning the GMD mission to Norad are unknown, that’s no reason the country should remain in the dark. Signalling to the U.S. publicly that Canada wants to participate in GMD opens the door for a well-informed policy decision. And the U.S. would have little choice but to respond positively given the importance it attaches to allied participation in GMD.