In the wake of the Paris attacks European security experts say the flaws in the continent’s defenses are conspicuous, with no clear plan for fixing them. “We lack the most obvious tools to deal with this threat,” Jean-Charles Brisard, chairman of the Paris-based Center for the Analysis of Terrorism, told the Washington Post. “We’re blind.”

The systems of European security that at one time were useful and effective are no longer adapted for this threat,” Bernard Squarcini, a former head of France’s domestic intelligence service who now leads the Paris office of the global intelligence firm Arcanum, told the Post. “We are dealing with people who are cunning and determined. They’ve been in combat.”

Security experts say that another large-scale attack in Europe is almost inevitable. European counterterrorism agencies, working hard to prevent such attacks, appear resigned to the fact that such attacks will happen.