BRIGHTON, England: The US and UK have over the past few weeks carried out a number of joint military strikes on Houthi targets in Yemen. The strikes have been in response to attacks by the Iran-backed Houthi rebels on both commercial and state vessels in the Red Sea since conflict broke out in Gaza on Oct 7, 2023.
The US and UK have justified their strikes by invoking the right of self-defence, as enshrined in Article 51 of the United Nations’ charter. The same right is also found within customary international law.
Together, the two sources provide that the right exists “if an armed attack occurs” against a state and that any action taken should be both “necessary” and “proportionate”.
On the face of it, this justification might seem relatively straightforward. But the reality is that the justification advanced by these states is far from clear and the applicable law not settled.
WAS SELF-DEFENCE JUSTIFIED?
The Houthis are in control of much of Yemen. But they don’t (yet, at least) represent the legally recognised government. While there is today much support for the argument that armed attacks that permit a state to act in self-defence can be perpetrated by non-state groups such as the Houthis, this is not a settled position.
Many states, commentators and even the International Court of Justice still require that such attacks be perpetrated by states or at least be attributable to a state through its effective control over attacks by non-state armed groups.
Whether Iran had this level of control over these particular attacks is not clear. But in any case, the US and UK response took place on the territory of Yemen, not Iran.