The Canadian newspapers reported this week that Prime Minister Netanyahu would be seeking the support of the Canadian government for a possible military attack on Iran. There is increasing speculation that Israel will launch military strikes before summer against the nuclear enrichment facilities within Iran, in an attempt to prevent Iran from developing nuclear weapons. Prime Minister Harper has given Netanyahu hope that Canada might back such a move. But the strikes would violate international law, and Canadian support for them would utterly betray the values that Canada has long championed.

First, let us examine the legality. The international law regime under the United Nations system prohibits all use of armed force, except in self-defence in the event of an armed attack, or for collective security purposes as authorized by the U.N. Security Council. The Israelis are trying to characterize the proposed military strikes as acts of self-defence to prevent an existential threat from materializing. Such strikes would not, however, satisfy the test for self-defence.

While there is some agreement in international law that states can use force to defend against an imminent armed attack, rather than being required to wait for the first blow to actually fall, the test for imminence is strict. Such "anticipatory self-defense" is permitted only when the "necessity of self-defense is instant, overwhelming, and leaving no choice of means and no moment for deliberation" (a formulation that arose from an incident between Britain and the U.S. in 19th-century Canada, as it happens). In contrast, there has been widespread rejection of the concept of "preventative self-defense" -- that is, the use of force to prevent the development of a more distant and speculative future threat.

The threat posed by Iran's possible development of nuclear weapons does not satisfy the "imminent armed attack" standard. There is still no conclusive evidence that Iran is developing nuclear weapons (as opposed to simply enriching uranium), and the U.S. intelligence community is not convinced that Iran has made the decision to develop nuclear weapons, given that it may be more in Iran's interest to stop short at "break-out capability." Even if the plan is to develop nuclear weapons, there is no sound evidence of any clear intention to use them against Israel or anyone else.

The historic evidence from states that have gone nuclear, including the case of Israel itself, reflects that countries seek to depend on the deterrence provided by nuclear weapons contemplate using them aggressively, and even tend to become more secure and less strident in their international affairs. The U.S. government itself has dismissed the notion that the Iranian regime is not a rational actor. There is still, of course, good reason to be concerned about the prospect of a nuclear-armed Iran, and the international community ought to continue to oppose such efforts. But the prospect of Iran obtaining nuclear weapons in the next year or two does not now rise to the level of being an imminent threat of armed attack, and military strikes against Iran are certainly not the "only alternative" to addressing the potential threat at this stage. Such strikes would be "preventative" at best, and are prohibited under international law.

The most recent condemnation of the "preventative self-defense" doctrine arose with the invasion of Iraq in 2003. The Bush administration argued in the run up to the invasion that it was justified on the grounds of "preventative self-defense," given the belief that the Hussein regime was on the verge of developing weapons of mass destruction. But in the face of withering criticism, neither the U.S. nor the U.K. actually tried to justify the legality of the invasion on such arguments, choosing instead to rely upon tenuous claims that prior U.N. Security Council resolutions authorized the action.

In a now-famous classified memo to Prime Minister Tony Blair, Attorney General Lord Goldsmith analyzed the legal justification for the use of force, and rejected the "preventative self-defense" arguments as being inconsistent with international law. In short, the potential possession of nuclear weapons by a regime that had invaded Iran in one of the bloodiest wars since World War II, then invaded Kuwait less than a decade later, and which had employed chemical weapons against its own people, did not constitute an imminent threat, or justify a "preventative use of force."

Twenty years earlier Israel itself had tested the doctrine. In 1981, Israel launched an air-strike against the Osirak nuclear reactor in Iraq. It did so on the same grounds as it proposes to use force against Iran today. The international community immediately condemned the Israeli strike as a naked act of aggression, with even the U.S. uncharacteristically voting in favor of a U.N. Security Council resolution condemning Israel's actions. Ironically, even though the strike severely damaged the reactor, evidence would later show that the attack caused Iraq to move its nuclear program underground rather than to discontinue it.

Canada has been a champion of the U.N. system since its inception, playing a significant role in its development. Canada has been a loud advocate for an international rule of law. On the issues of war and peace, it has carved out a role as honest broker and peacemaker within the U.N. system, symbolized most clearly with Lester Pearson's winning of the Nobel Peace Prize for his role in resolving the Suez Crisis in 1956, and the establishment of the first U.N. peacekeeping force. More recently Canada's values were reflected in the decision not to participate in the arguably unlawful war against Iraq in 2003. Far less known is the role that Canada has played over the years in negotiations surrounding the Nuclear Non-Proliferation Treaty, and nuclear disarmament issues.

The idea that Canada would now support an unlawful act of aggression by Israel, itself a nuclear power that has rejected the Nuclear Non-Proliferation Treaty regime, based on arguments that Iran is violating its obligations under that same treaty, should be abhorrent to most Canadians. It would not only put Canada in the role of endorsing a violation of the U.N. Charter's most fundamental prohibition, but it would also utterly shred our credibility as an honest broker in the region, and in our role as a middle power on nuclear disarmament and non-proliferation issues.

Canada would, moreover, be out in front helping to facilitate illegal actions that could lead to severe international disruption. The U.S. and U.K. governments have been trying to discourage the Israeli attacks precisely because of fears that they would not prevent the Iranian development of nuclear weapons, but would only cause serious retaliation against Israel as well as the U.S. and other Western states, and possibly lead to the eruption of wider armed conflict in the region. The impact on the global economy and peace in the region are difficult to predict but could be catastrophic. Canada must not play a role in contributing to such a turn of events.

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