What would it take to justify the killing?

As implied in my previous blogpost, the Pentagon had justified the strike by saying that it was “aimed at deterring future Iranian attack plans.” The DoD had also claimed that Soleimani was “actively developing plans to attack American diplomats and service members in Iraq and throughout the region”.

The debate, in particular in the US, now seems to be about whether there was proof about such plans. As I argued Friday (para 5), even if there were such plans, the strike would have been illegal.

Another possible ground is that the US was already involved in a violent encounter with Iran, was also suggested in the statement, since Soleimani allegedly had “orchestrated” attacks against Iraqi and US personnel, including the one on 27 December. If that had been the case, there would already be an armed conflict, and the US could justify the killing under the laws of armed conflict (my para 2). However, the US itself has not claimed that it was acting under those laws, since it has not invoked the laws or armed conflicts, nor used the pertinent terms “belligerency”, “armed attack”, “armed conflict” or the more colloquial word “war” (see here and here). In addition, even if it had invoked those rules, it would still have to show that the armed struggle betweeen the two parties reaches that level.