The weapons are increasingly ordinary — rented vehicles, nails and canisters, store-bought knives. A series of small-scale attacks has left Europeans trying to balance their desire not to give in to extremism with a persistent anxiety that it could strike at any time.
Even though a nail bomb didn't fully go off in Brussels Central Station late Tuesday and failed to hit dozens of commuters close by, it didn't stop fear going up a further notch.
And across Western Europe where the summer tourism season is about to start, the challenge is how to deal with it without having a big impact on daily life.
"We have to see in what kind of society we want to live in," said Belgian Interior Minister Jan Jambon. "Today it is train stations. Tomorrow all subway stations and the day after all city halls. Will we have to arm, protect, control all that? Is that the type of society we want," he asked.
Still, for Wednesday at least, more security was the way to go.
"Extra security measures have been decided for the coming hours and days," said Belgian Prime Minister Charles Michel after a 36-year-old Moroccan national shouting "Allahu akbar" set a bomb among commuters. The bomb didn't detonate in full and a soldier shot the man dead.
Those measures come on top of ones that have been in place under the second highest level of terror alert since twin bomb attacks killed 32 people in Brussels in March last year.
In sweltering heat, fans lined up early for security checks as they attended the first of two concerts by the band Coldplay at the 50,000-seater King Baudouin Stadium Wednesday night, with the concerts becoming another test of police security and public mettle.
In Paris, a day after a man with a bomb-rigged car tried to attack gendarmes on the Champs-Elysees, the iconic shopping avenue was filled with French and foreign visitors.
The succession of attacks in western European capitals like London, Paris and Brussels has become so numbing that Paris criminology Professor Alain Bauer is comparing it to living in London during World War II when German planes would relentlessly bomb the city in what became known as the Blitz.
During the Blitz, Bauer said in an interview. "The question that was asked was not to know whether there would be bombings, but how to endure them, resist against them, stand up against them with the idea that at the end, they would win," he said of the Londoners.
Even though the huge attacks like the November 2015 series in Paris that killed 130 have not returned, a different way to spread terror has come.
"We have gone from hyperterrorism or gigaterrorism to lumpenterrorism, low-intensity terrorism of proximity, with few victims but with a strong media amplification," Bauer said.
"A failed attack, a successful attack, an attack that has one victim or one that has 100, has the same media coverage," securing success for the attackers, Bauer said.
Still, people are starting to adapt to the attacks.
Remy Bonnaffe had just walked away from the timetable board at Brussels Central Station late Tuesday when he heard a loud bang and saw a flame. He took time to take a photo, thinking it could be useful to warn other commuters on Twitter about further delays.
"With all these events happening, at least for myself I have been thinking a lot 'what would I do if I would be in a situation like this'," he said in an interview with The Associated Press. "There were a couple of things I was really thinking about doing, like looking for cover and finding the nearest exit and things like that."
It is a kind of way of life that Prime Minister Michel says more and more people have to adapt to. "In three years we have been confronted with several attacks or attempts and we say the zero risk does not exist."
Hinnant reported from Paris. Virginia Mayo in Brussels contributed