Although disaster scenarios had been prepared, Belgian and European leaders failed to prevent the terrorist attacks from occurring.

Since the Paris attacks in November, 2015, Belgian police have cooperated with French and European police (Europol) in hunting down terrorist suspects in Brussels, which led to the arrest of Salah Abdeslam. But a few days later bomb attacks struck Zaventem airport and Maelbeek metro station in downtown Brussels, killing or wounding dozens of people. 

The attacks, which targeted a highly secured international airport and a metro station near the EU headquarters, were a direct challenge to Belgian and European authorities.

The attacks in Brussels demonstrate the vulnerability of France, Belgium, and other European countries to terror attacks. The fact that Salah Abdeslam’s hideout in Brussels went undetected for 4 months shows that the extremists have a solid network for hiding criminals and have established a terrorism center inside Europe.       

Europeans have widely differing viewpoints on terrorism risks and countermeasures. Some people want controls aimed at specifically at Muslims. 
Others want to avoid polarizing Europe’s population by treating all Muslims as potential terrorists. More and more migrants are entering Europe from the Middle East and Africa, but no single agency is in charge of distinguishing war refugees, economic refugees, and religious extremists or IS members. 
Though many meetings have been held within the EU and between the EU and partners like Turkey, no way has been found to stem the migrant flow. 
Refugee policies differ among EU countries. Some want to close their borders. Some want to rescind the Schengen free travel agreement. Others have proposed deporting the migrants. 
All are concerned about the terrorism risk posed by extremists who may be among the migrants.