After the terror attacks in Paris last November, The Independent concurred with President Hollande’s verdict that these atrocities were an act of war. The suicide bomb attacks in Brussels on Tuesday were another event in the same war: same aggressors, similar innocent victims.

Acceptance that we are in a war makes such murderous events both easier and harder for us to deal with. Easier, because no war ends with a single battle, so unconsciously at least we were braced for further such atrocities, as the speed at which the Brussels metro returned to normal service suggested. But if these warlike events, stretching back to the 9/11 attacks in the US and the 7/7 attacks in London, are understood as battles in an ongoing war – and both the public and the authorities are aware that this is the case – it becomes harder to accept the failure of those responsible to take the necessary steps to bring the war to an end.

As our Middle East correspondent Patrick Cockburn has argued, we and our allies share a grave responsibility for creating the circumstances in which Islamist terror groups can thrive, and then refusing to learn the lessons of those mistakes.

The invasion of Iraq, where jihadi terror had barely a toehold under Saddam Hussein, created a power vacuum and a seething population of resentful Sunni Muslims, which proved the perfect ground for Isis to emerge and flourish. We went on to make precisely the same errors in Libya, with the same consequences – a grotesque error for which David Cameron has never publicly apologised. Indeed, only the wisdom of the House of Commons balked him from doing precisely the same thing all over again in Syria, eliminating the Assad regime and thereby throwing down the welcome mat to Isis in Damascus. Even today there is no indication that he and his colleagues are aware of how much more dangerous their actions have made the situation in Europe.

But given the fact that terror is today being manufactured and exported from Iraq and Syria in industrial quantities, the other, equally grave problem is that Europe has utterly failed to forge an adequate response to it.

Brussels attacks: tributes are paid to the victims Show all 27 1 /27 Brussels attacks: tributes are paid to the victims Brussels attacks: tributes are paid to the victims Wreaths of flowers in front of an entrance of the Maalbeek subway station in Brussels in homage to the victims of a terrorist attack. Getty Images Brussels attacks: tributes are paid to the victims Wreaths of flowers in front of an entrance of the Maalbeek subway station in Brussels in homage to the victims of a terrorist attack. Getty Images Brussels attacks: tributes are paid to the victims A building illuminated with the Belgian flag colours and a heart in Brussels, two days after suicide bombing attacks of terrorists on March 22 in Zaventem airport and subway Maelbeek. Getty Images Brussels attacks: tributes are paid to the victims A picture taken on 24 March, 2016 on place de la Bourse in Brussels, shows drawings and a candle, two days after suicide bombing attacks of terrorists on March 22 in Zaventem airport and Brussels subway Maelbeek Getty Images Brussels attacks: tributes are paid to the victims Candles are displayed in tribute to the Brussels attacks victims on 24 March, 2016 on place de la Bourse in Brussels, two days after the suicide bombing attacks of terrorists on 22 March. Getty Images Brussels attacks: tributes are paid to the victims A mourner lights a candle in Trafalgar Square during a candlelit vigil in support of the victims of the recent terror attacks in Brussels. Getty Images Brussels attacks: tributes are paid to the victims Brussels airport workers pay tribute to the victims near Zaventem Getty Images Brussels attacks: tributes are paid to the victims Activists light candles and hold placards to condemn the terrorist attacks in Belgium, during a gathering in Manila, Philippines Brussels attacks: tributes are paid to the victims A banner for the victims of the bombings reads "I am Brussels" at the Place de la Bourse in the center of Brussels Brussels attacks: tributes are paid to the victims European Commission President Jean-Claude Juncker, left front center, stands with front row, left to right, French Prime Minister Manuel Valls, Belgium's King Philippe, Belgium's Queen Mathilde and Belgian Prime Minister Charles Michel as well as members of the European Commission during a minute of silence at EU headquarters in Brussels Brussels attacks: tributes are paid to the victims People join hands in solidarity near the former stock exchange following the bomb attacks in Brussels Brussels attacks: tributes are paid to the victims Belgium flags ornate the facade of the Paris Town Hall Brussels attacks: tributes are paid to the victims A woman embraces her children at The Place de la Bourse as she pays her respects to victims of the terrorists attacks in Brussels Brussels attacks: tributes are paid to the victims Belgian and European Union flags fly at half mast following the bomb attacks in Brussels Brussels attacks: tributes are paid to the victims Candles in the colors of the Belgian national flag are lit inside the Belgian embassy in Madrid, a day after the deadly suicide attacks on the Brussels airport and its subway system Brussels attacks: tributes are paid to the victims Servicemen of Azov, Ukrainian volunteers battalion, hold torches in front of floral tributes during a ceremony in front of the Belgian embassy in Kiev, in tribute to the victims of Brussels attacks Brussels attacks: tributes are paid to the victims A refugee boy holds up a placard reading "Sorry for Brussels" at a refugee camp near the Greek-Macedonian border Brussels attacks: tributes are paid to the victims Brussels tributes People light candles in tribute to victims at a makeshift memorial at the Place de la Bourse in Brussels Getty Images Brussels attacks: tributes are paid to the victims Brussels tributes A woman holds a drawing by French cartoonist Plantu picturing a character made of a French flag consoling another made of the Belgian flag, in front of the Hotel de Ville in Paris Getty Images Brussels attacks: tributes are paid to the victims Brussels tributes The colours of the Belgian flag are projected on to (clockwise from top left) the Eiffel Tower in Paris, the town council building in Belgrade, Rome's Campidoglio and the Royal Palace at Dam Square in Amsterdam Getty Images Brussels attacks: tributes are paid to the victims Brussels tributes Candles are lit in tribute to the victims, at the Place de la Bourse in Brussels Getty Images Brussels attacks: tributes are paid to the victims Brussels tributes A woman holds a placard reading "Paris hearts Belgium, How much time will it take us to open our eyes and say STOP, Today our hearts are broken, Open your eyes to change the future" at the Place de la Republique in Paris Getty Images Brussels attacks: tributes are paid to the victims Brussels tributes People gather to pay a tribute to victims of terrorist attacks in Brussels Getty Images Brussels attacks: tributes are paid to the victims Brussels tributes People write messages on the ground at Place de la Bourse in Brussels Getty Images Brussels attacks: tributes are paid to the victims Brussels tributes A bouquet of flowers in the Belgian national colours with a card reading 'To our neighbours, to our friends, to our Belgian brothers - an indignant Parisian' is seen next to a French national flag at the fence of the Belgian embassy in Paris Getty Images Brussels attacks: tributes are paid to the victims Brussels tributes Solidarity messages are written in chalk outside the stock exchange in Brussels AP Brussels attacks: tributes are paid to the victims Brussels tributes Messages and floral tributes outside the Brussels stock exchange AP

Turkey deported Brahim el-Bakraoui, one of the Brussels bombers, to the Netherlands last year, but despite overt warnings by Ankara that he was a terrorist fighter, he was able to go about his business, which culminated in him blowing himself and others up at Brussels Airport. One might fondly suppose that the erosion of national borders in the EU would facilitate the continent-wide struggle against the terrorists, but the opposite seems to be the case: while Schengen permits the killers to slip in and out of any country they fancy, the EU’s counter-terrorism co-ordinator was dismissed in a recent French parliamentary report as “weak” and “having no operational capacity to offer”. Nigel Farage’s comment about the “free movement of Kalashnikovs” was crassly timed but essentially correct.

Like other vital EU arms such as Frontex, the border control agency, the counter-terrorism co-ordinator is disastrously weak, as weak as the union’s weakest link. And few links are more treacherous than Brussels: heart of the union, and so dysfunctional in its policing that Molenbeek, where much recent terror has been incubated, has been a no-go zone for decades.