Just for curiosity's sake, did any other EU countries have any recent terrorist attacks involving bombs on trains in the capital, or is Spain so far alone with this experience?
Edit: Also, after looking it up, it seems like London did add temporary security scanners at some locations in the wake of those bombings, although they weren't permanent.
Russia is the only other European country besides Spain that after train bombings added permanent security scanners. Belgium, France and a bunch of other countries have had train bombings, but none of them added permanent scanners like Spain or Russia did.
Notice how these inefficient processes create large, compact lines of passengers, which would made the casualties much worse in case of an actual bomb.