Last week’s tub-bomb on the Tube is this month’s reminder of our generational struggle. So why have we not yet thrown the full weight of international law against our enemies with prosecutions for genocide?

No-one now disputes genocide is the crime we can hang around the neck of Isil’s army of evil. The House of Commons, the European Parliament, the Council of Europe, the US Congress, and the national assemblies of France, Austria, Lithuania, Canada and Australia have all condemned Daesh’s actions as genocide, along with Pope Francis.

If we cannot convict Daesh itself, let’s at least hand over British nationals to the ICC wherever and whenever we can.  Convictions for genocide or war crimes will send the clearest message, defining the character of the enemy we face. And our determination to win.