THERE are some occasions in history when the world stands still, frozen, aghast at the awfulness of what has happened, at the sheer inhumane brutality of it. The assassination of JFK; the death of Princess Diana, 9/11, 7/7, Charlie Hebdo, and now most chillingly brutal of all, Paris on Friday 13th. We mourn with the French; we stand shoulder to shoulder with them, not least because “there, but for the grace of God, go I.”

But what now? My role in multiple defence matters in Parliament means that I was wrestling with worries before Friday, which are now compounded. Should we smash ISIS with military force? If so, how do we stop an equally hideous hydra appearing in its place? How can we stabilise Syria without siding with one of the worst dictators since Hitler, Bashar al-Assad?

Should we now mend our fences with Putin, in which case would we not risk encouraging Russian military incursions in the Baltic states, which, of course, are NATO and EU members, thereby risking massive escalation? Should we really insert ourselves between Sunni and Shia? Yet there is no logic in bombing in Iraq, but leaving the Americans to kill Jihadi John because he happens to be in Raqqa in Syria at the time.

Russian bombing in Syria very probably led to the downing of the Sharm el-Sheikh plane with a loss of 224 innocent Russian lives. French bombing in Syria is probably partly to blame for the Paris atrocity and at least 129 lives.

Yet let us never forget that Peshmerga advances in Iraq and the killing of senior ISIS personnel there and in Syria is at least partly thanks to British military assistance and efforts. Daesh have their backs to the wall to a degree in the Middle East, and the serpent is striking out elsewhere as a result.

But the atrocity and its aftermath have wider implications than the purely military. The tide of migrants must be stopped, not least because it has become clear that some part of them are ISIS terrorists. But how do you stop it? And where do they go? What happens to the millions of innocent refugee women and children? And what do you do about those who may well be here already? What does it all mean for the future of the Schengen Agreement (surely it cannot survive) and perhaps of the EU as a whole? Does its existence and our membership of it help at a time like this? Or do these matters demonstrate how useless and pointless it all is?

The world is indeed in turmoil; and that turmoil is now lapping at our shores, knocking down our front doors. Now must be the time for mourning for the French; for urgent action against criminals and terrorists on our own territory; for stronger defence against migrants; for determined action against murderers in the Middle East and elsewhere. But it is also the time for cool, quiet reflection and analysis. Knee-jerk military reactions in the short term without deep planning for its purpose and future would be the worst of all possible outcomes.

Now is indeed the time for the world to stand still, to grieve, and to plan. We need a strong arm but a cool head to govern it.