Prime Minister Mark Carney’s anti-Israel bias has been evident on several occasions over the past year. While he may be an economist, Canadians have a right to expect that their prime minister at least have advisors who instruct him in international law before he stakes out a position on behalf of his government and country.
When Carney recently denounced Israel’s entry into southern Lebanon to clear out Hezbollah positions that had launched thousands of rockets into Israel as a violation of Lebanon’s sovereignty and an “illegal invasion,” he was wrong. Dead wrong.
International law is often invoked as a restraint on the use of force. Less frequently acknowledged — but equally central — is that it also provides states with the right to defend themselves in specific circumstances when attacked. That right does not evaporate when the source of violence lies just across a border, particularly when the neighbouring state is unwilling or unable to act.
The specific circumstances in international law include, self-defence, anticipatory self-defence and global non-international armed conflict such as occurred when the United States, Canada and other allies went after Bin Laden in Afghanistan and ISIS in Iraq and Syria.
On self-defence, in the post-9/11 era we have seen it in state practice. Not just by the Americans, but by the French in Mali, and by Canadians and others in Afghanistan. Anticipatory șelf-defence includes imminent and ongoing threat. By the United Nations Interim Force in Lebanon’s (UNIFIL) numbers — not Israel’s alone — Hezbollah has launched thousands of rockets at Israel. It proudly boasts of it.
As far as sovereignty is concerned, that is a claim for Lebanon to make — not Canada. Unless the prime minister is somehow appropriating a new role as a global policeman, something he has criticized America for.
At the heart of these international legal principles is Article 51 of the United Nations Charter, which affirms the “inherent right of individual or collective self-defence” if an armed attack occurs. While originally conceived in a world of state-on-state conflict, the doctrine has evolved to address a persistent modern reality: non-state actors launching attacks from within sovereign territories.
Terrorist organizations — from insurgent militias to transnational jihadist networks — rarely operate in a vacuum. They embed themselves within weak, failed or complicit states. Hezbollah in southern Lebanon is a paradigmatic example: an armed non-state actor exercising de facto control over territory, maintaining an independent military capacity and conducting cross-border attacks against Israel while the central government proves unable — or unwilling — to restrain it.
This is precisely the scenario in which the law has had to adapt. A broad and growing consensus among states recognizes what is often called the “unwilling or unable” doctrine. Where a host state fails to suppress the threat, the victim state may use force within that territory, provided its actions meet the established criteria of necessity and proportionality. And just to be clear on the latter which so many commentators get wrong, proportionality in international law is based on being proportional to the military objective sought to be achieved.
That principle is not merely theoretical. It is reinforced by binding Security Council decisions. UN Security Council Resolution 1373 (2001), adopted after the September 11 attacks, obliges all states to prevent and suppress terrorism, including denying safe haven to those who plan or support attacks. When a state fails to meet that obligation, it is not simply failing to exercise sovereignty — it is breaching a duty owed to the international community.
The case of Lebanon is even more specific. Following the 2006 war between Israel and Hezbollah, the Security Council adopted Resolution 1701. That resolution explicitly calls for the disarmament of all armed groups in Lebanon other than the Lebanese state and mandates that no weapons be present south of the Litani River except those of the Lebanese armed forces and UN peacekeepers. Nearly two decades later, that obligation remains unfulfilled. Hezbollah has not only retained its arsenal but significantly expanded it.
This matters legally. When a state accepts binding obligations — whether through Security Council resolutions or international conventions — it assumes responsibility for ensuring compliance within its territory. Failure to do so is not a neutral fact; it has legal consequences. It strengthens the case that the state is “unable” in the sense relevant to the law of self-defence.
Additional legal frameworks reinforce this duty. The International Convention for the Suppression of the Financing of Terrorism (1999) requires states to prevent and punish the funding of terrorist acts. The broader corpus of counterterrorism treaties — along with customary international law — imposes a due diligence obligation: states must not knowingly allow their territory to be used for acts contrary to the rights of other states.
Even earlier instruments point in the same direction. The 1970 UN General Assembly Declaration on Friendly Relations affirms that states have a duty to refrain from organizing, assisting or tolerating acts of armed force against other states. Sovereignty, in other words, is conditioned on responsible conduct.
Critics argue that invoking self-defence across borders risks eroding the prohibition on the use of force. That concern misinterprets the balance the law seeks to strike. The prohibition on force and the right of self-defence are not in tension; they are complementary. One prevents aggression. The other permits defence.
The alternative is untenable. If international law were interpreted to prohibit cross-border action in all circumstances, states would face an impossible choice: absorb repeated attacks or violate the law to stop them. That is not a stable or credible legal framework. International law reflects reality, it does not deny it.
Of course, the right of self-defence is not without limits. The Geneva Conventions and its additional protocols, particularly Protocol 1, require distinction, necessity and proportionality. Force must be directed at the threat itself, not used as a pretext for broader objectives. Civilian harm must be minimized, and actions must be calibrated to the scale of the attack. But the Conventions do not require surrender in the face of aggression. Proportionality itself is based on what is proportional to the military objective. No nation in history has taken the measures Israel has to minimize civilian harm as Israel does including sending out electronic telephone maps of blocks and buildings it plans to strike and giving time for civilians to get out of the way.
Not only does Israel have a legal right to enter Lebanon to eliminate Hezbollah, but once its forces are physically in control of territory, it may occupy territory under the applicable rules of the law of occupation primarily under the Fourth Geneva Convention and the Hague Regulations of 1907. The key principles are that occupation be temporary, there be no transfer of sovereignty, order and civil life must be maintained and no permanent changes be entrenched unless militarily necessary. In fact, the United States, Canada and its allies invoked Article 51 of the UN Charter and these Geneva and Hague regulations to justify their some 20-year-long occupation of Afghanistan.
As much as Prime Minister Carney may like to, he cannot invoke a double standard against Israel. The central principles remain clear. International law does not demand passivity in the face of attack. It does not grant terrorist groups a de facto sanctuary simply because they operate from within another jurisdiction. It does not require states to tolerate attacks launched from beyond their borders. It does not allow sovereignty to be weaponized as a shield for armed groups. It does not strip states of the right to defend their citizens simply because their attackers exploit jurisdictional lines. And it does not allow sovereignty to be weaponized as a shield for ongoing violence.
In a world where armed non-state actors exploit borders with increasing sophistication, the law of self-defence must be understood in practical terms. Sovereignty entails rights — but also obligations. When those obligations are not met, the right of self-defence does not stop at the border.
It cannot.
National Post
Beryl P. Wajsman, B.C.L., LL.B., KCR is president of the Institute for Public Affairs of Montreal.