Why U.S. Missile Strikes on ISIS in Nigeria Don’t Violate International Law (in 2 minutes)
By Yusra Suedi (PhD, Assistant Professor of International Law at University of Manchester)
The U.S. just delivered a Christmas gift to Nigeria, launching missile strikes against Islamic State (i.e., IS/ ISIS/ ISIL/ Daesh) terrorists operating in the northwest.
According to Trump, the aim of the strikes were to stop the killings of Nigerian Christians - although the Nigerian government says the strikes were ‘not intended to protect any specific religions’.
I know what you’re thinking: “another illegal U.S. use of force?”
Actually, no. (I know, shocker.)
Let’s break it down, simply.
This is a use of force
There’s no getting around this part.
Firing missiles into another country is obviously a use of force under international law.
This is prohibited, unless an exception applies.
The key exception is consent
The exceptions most people immediately think of are self-defence or UN Security Council authorisation.
But there’s another often overlooked one: Consent.
If the government of Nigeria consented to U.S. strikes on its territory, then the use of force is not unlawful.
And in this case, Nigeria did more than merely consent. According to public reporting, the operation was jointly planned and coordinated by the US and Nigeria!
Under international law, consent makes the use of force lawful because the country where it happens has agreed to it.
When is consent legally valid?
For consent to be legal, several conditions must be met:
First, it must come from the legitimate government of Nigeria. Check.
Second, it must be freely given. Check - there’s no indication of coercion.
Third, the operation has to stick to what Nigeria actually agreed to, i.e., only going after IS fighters, staying on Nigerian soil, and following any limits set on timing, location, or how the strikes are carried out.
Public statements by the Nigerian government suggest that the operation stayed within the agreed framework.
But can the US use force against a group, not a state?
Yes.
International law traditionally focused on one country using force against another country.
But modern practice has long accepted that force may be used against non-state armed groups operating within another country.
This is now routine in counter-terrorism operations worldwide.
So the fact that the targets were ISIS fighters, rather than Nigeria itself, is not legally controversial.
But… ‘legal’ doesn’t mean ‘anything goes’!
Consent cannot justify the US/Nigeria committing international crimes to reach those ends.
In practice, that means the strikes must respect basic rules like targeting only fighters and avoiding excessive harm to civilians.
Nigeria’s human rights obligations towards its population also continue. So it must do everything to protect its civilians.
Reports indicate that the attacks were pretty precise.
If that’s correct, then, based on what we know, the strikes are lawful under international law.
The U.S. has announced that more strikes are coming. Gulp! As usual, SAIL will be analysing events as they unfold.
Had fun reading the piece. I am a bit confused as to how a state can use force against a non-state actor. I understand that in contemporary international law, it is widely practiced and tolerated. But Articles 2(4) and 51 specifically engage states as confirmed by the Wall AO. So, what is the status of this practice now, is it a customary principle now?