The past few weeks will likely be remembered as one of the most difficult times in recent European history. First the November 13 attacks on Paris that claimed the lives of 130 people and left hundreds more wounded; then the bomb scare at the Germany-Netherlands soccer game in Hannover; the lockdown of Brussels; the ruthless manhunt for the surviving terrorists and their accomplices. And in between – police searches, arrests, army patrols, curfews and countless false alarms.Only the past few of days saw Europe inching back to normality. In Brussels, schools, shops and public offices re-opened after days of forced inactivity. The media are shifting their focus back to business-as-usual topics – the summit on climate change, local political disputes, crime news. Yet, although recovery is underway Europe is waking up to a new reality.For quite some time the Old Continent had been the land of peace and stability par excellence. Until recently Islamic State and al-Qaida, Assad and al-Baghdadi, Syria and Iraq were, for most people, foreign names and remote places popping up every here and then in the headlines. There had been threats and warnings of potential attacks in European cities, but the idea seemed inconceivable.Then the attacks on Charlie Hebdo and Hyper Cacher last January suddenly brought the Middle Eastern turmoil one step closer. What was happening on the other side of the Mediterranean became more relevant and worthy of attention. “Je suis Charlie” everyone chanted.Yet the attacks had no tangible impact on the lives of the average European. Europe still felt safe. In the end, there was an easy explanation for why the terrorists had picked those targets. They accused the satirical magazine of insulting Prophet Muhammad with its blasphemous cartoons. As for the kosher supermarket – it is no mystery that Jews are among the favorite targets of Islamic extremism.This time though, it was different. The terrorists in Paris struck aimlessly and killed indiscriminately: French and foreigner, young and old, men and women.Not because of something their victims were doing or had ever done, but because of who they were – infidels.Therefore, anyone crossing the terrorists’ path could become a potential victim.So the reason why, despite the recovery, Europeans today seem more confused and disoriented than ever is that they realize that nobody is safe anymore – nobody is immune. In the blink of an eye, anyone could become the next victim of jihadist fury. And that is a feeling that Western societies are completely unfamiliar with.Their question is – what’s next? Is it going to happen again? Political leaders may reassure their people by deploying more police on the streets, by reviewing security measures at the borders, by increasing the level of cooperation with foreign governments and intelligence agencies. But the hard truth – a truth that no politician will ever admit – is that the war on terror is a fight they cannot win. In fact it is nothing more, and it cannot be anything more, than mere damage control.Of course it is possible to invest a great amount of resources in prevention, but with no guarantees of absolute security. The only way to make a liberal society entirely immune to terrorism would require restrictions on movement, communications and personal freedoms that no democracy could ever accept.But without such measures it is enough for one terrorist to slip through the cracks of the system and we could have another massacre. To paraphrase the chilling words used by IRA terrorists back in the 1980s – in order to win this game, counterterrorism has to be lucky every time, but terrorists have to be lucky just once.So this is the catch of terrorism.On one side, we have one of the primary functions of a state – providing security to its citizens. On the other, we have a set of liberties and values that we cannot renounce. And in the middle is an enemy who is taking advantage of this basic paradox of our societies, forcing us to choose between the two.What is the right approach? Is a balance between liberalism and security even possible? Maybe it is, or maybe not. Perhaps though, today European leaders will understand better the kind of dilemma that Israel has to face – every single day.The author recently obtained a Master of International Affairs in International Security Policy from Columbia University in New York.Twitter: @davbraha.