The present contribution is a reply to an article by Professor Michael Mandel, entitled "Aggressors' rights : the doctrine of "equality between belligerents" and the legacy of Nuremberg". The equal application of international humanitarian law (jus in bello) to all parties to an international armed conflict is a cornerstone principle of jus in bello. In his article, Professor Mandel casts doubt on the legal basis of this principle. Reacting to this claim, this contribution demonstrates that the ‘equality of belligerents’ is a principle firmly grounded in both conventional and customary international law. Moreover, its legal force withstands the test of international jurisprudence, including the International Court of Justice's controversial Nuclear Weapons advisory opinion.