Outside the Bataclan theatre, the scene of one of the attacks (photo: Anna Harada Viot)

New York and Washington 2001; Madrid 2004; London 2005; Mumbai 2008; Toulouse 2012; Brussels 2014; Paris 2015; Copenhagen 2015; Sousse 2015; Sinai 2015; Beirut 2015. And now Paris again. Last month’s attack, even more devastating than January’s, has not broken French resistance: reports that Parisians were “gripped with fear” were false. But President Hollande’s declaration of war may be just an escalation in rhetoric.

How much havoc do the jihadis have to wreak before Europe and America resolve to tackle the source of the evil: the ideology of Islamism itself? How many have to die or be maimed — some 500 people in the Paris atrocity alone — before Western leaders recognise that the self-proclaimed Caliph Ibrahim, alias Abu Bakr al-Baghdadi, and his butchers of Islamic State wish to kill us — all of us, “Jews and crusaders” alike — not because of what we do but because of who we are?

This month’s Standpoint is dedicated to the victims. They deserved better of our leaders, most of whom have pretended that we were not engaged in a fight to the death against radical Islam. As the smoke cleared over Paris, President Obama was repeating his mantra that this had been an attack “on all of humanity and the universal values that we share”. No, Mr President: it was an attack targeted at Western civilisation, whose values are certainly not universally shared. Unless the free world’s leaders, above all the US commander-in-chief, defend those values, Islamists will only become more murderous — until we cashier the old leaders and find new ones.

What forms might such action take? We could do much more at home — if we keep our nerve. It is rare to see armed police or troops, let alone the SAS, on the streets of London. Police searches of mosques and in predominately Muslim neighbourhoods are even rarer. We shall have to get used to such things. There must be no deference to those who are harbouring terrorists or who are recruiting Islamist volunteers for Syria. Too often radicals “known to the police” resurface as terrorists. Not only policing but the law itself is unfit for purpose. Treason sounds harsh, but what other word fits the heinous crime of making war, by word or deed, against one’s own country? The time has now come to modernise the law of treason to defend our way of life.

There has been much debate about the proper limits that our intelligence services should observe in seeking to prevent such attacks. The services are mocked as “snoopers” by the human rights lobby, privacy campaigners and the rest. Only those who have never been on the receiving end of a terror attack could think that there is any “balance to be struck” between the threat of such violence and the pernicious notion that Western intelligence agencies are engaged in a sinister conspiracy to invade our private lives. In Israel, where vigilance is second nature because Jews have always struggled for survival against a hostile world, most people are relaxed about, even reassured by, security measures. As Islamists grow bolder, we shall have to learn to keep calm and let those whose job is to protect us carry on.