This is a guest post by Betcy Jose, Assistant Professor at University of Colorado-Denver and author of Norm Contestation: Insights into Non-Conformity with Armed Conflict Norms. Follow her on Twitter.

After the recent strikes in Syria, Germany’s Angela Merkel stated the intervention was, “necessary and appropriate, to ensure the effectiveness of the international ban of chemical weapons use and to warn the Syrian regime of further violations.”   UN Secretary-General Antonio Guterres remarked,  “A lack of accountability emboldens those who would use such weapons by providing them with the reassurance of impunity.”   However, some members of the international community felt differently about the strikes.  Russia sponsored a UN Security Council (UNSC) resolution condemning the strikes as a violation of the non-intervention norm which was rejected.

Did the missile strikes violate the non-intervention norm?   Article 2(4) of the UN Charter essentially permits two exceptions to the non-intervention norm, considered norms in their own right: violations occurring with UNSC approval and for self-defense.  None of the participating states made a self-defense argument. Neither did the intervention receive UNSC authorization. Thus, one could conclude that the intervention was inconsistent with the non-intervention norm and its exceptions.  So what then are we to make of statements like Merkel’s or the rejection of the above UNSC resolution?

Norms scholars would tell us that acceptance of norm violations or silence to them suggests weakening norms.  And if the violation engenders approval, it may also set the stage for new norm emergence. Support for the strikes suggests shifts in intersubjective agreement, shared and accepted understandings of the appropriate ways actors ought to behave.  The endorsements above suggest some in the international community may be willing to loosen their commitment to the UNSC normative exception under specific circumstances.  And in doing so, they may weaken it and the non-intervention norm, enabling new avenues for permissibly violating state sovereignty.

I argued that we saw a similar pattern with bin Laden’s death.  Before he died, U.S. and Israeli targeted killings often faced immediate scrutiny and/or condemnation because many felt they violated existing human rights norms.  With his death, we witnessed quite different reactions.  Support or silence to his death came from surprising directions including Russia, Germany, and the UN.  This reactional change might be partially linked to how much the international community detested bin Laden.  His death served as a window of opportunity to help shift intersubjective agreement on the practice’s merits that the US and Israel consistently advanced prior to his death.

Chemical weapons use in Syria could similarly trigger changes to intersubjective agreement on the UNSC norm.  The chemical weapons taboo is quite strong, as indicated in both Merkel’s and the UN’s statements.  Further, Syrian President Bashar al-Assad is strongly disliked enough and the Syrian conflict destabilizes the international system sufficiently to compel some of its members to loosen their fidelity to the non-intervention norm and its current exceptions.

Of course, a single act may not always suffice to weaken well-established norms and usher in a new one.  Friday’s strikes and the reactions to them alone won’t modify intersubjective agreement on the non-intervention norm’ parameters. However, those strikes are not the only recent violations of the non-intervention norm and the UNSC norm receiving acceptance. Almost exactly a year ago, the United States engaged in similar action with similar global reactions.  And interestingly, parallels exist between the UK case for the missile strikes and Russia’s justifications for its Crimean intervention: both states declared the humanitarian crisis was dire enough to forego UNSC approval.

In the present case, it may not be so much that a new exception to the non-intervention norm is emerging as much as a previous norm is regaining acceptance.  Prior to the creation of the UN, select states took it upon themselves to regulate the international arena, producing some deeply destabilizing effects on the international system.

The jury is still out on whether we will see sustained changes in existing intervention-related norms.  The chances increase if justifications for going around the UNSC become clearer and more consistent (in addition to preserving the chemical weapons taboo, some actors invoked civilian protection more broadly for the intervention).  In any case, these events do present norms scholars opportunities to study not just norm enforcement but norm change.

Additionally, these events require us to evaluate the political actors’ norm-related claims.  If the international community is willing to weaken the non-intervention norm and its exceptions for humanitarian reasons, it has to decide what do with gaps between humanitarian rhetoric and action.  Further, we need to weigh the effect an altered non-aggression norm may have on global order.  After all, there is a reason why the earlier norm allowing unilateral war to punish international law violations died alongside the millions of people killed in both world wars.  And perhaps more importantly, it also has to ask itself why only some kinds of civilian suffering are worthy of such profound changes in the global order and not others.