I have 2 in-law relatives who live in Spain. Like most of Spain they were involved in the mass demonstrations of grief about the train bombs.
Yesterday on the news I heard 3 different reports claiming first that the bombs were planted by Al Qaeda ), then by ETA (Basque separatists, now probably Al Qaeda put for political reasons they are blaming ETA...
One of my relatives has also decided it is Al Qaeda and has reported back to us 'facts' which prove this. This relative is married to a Basque woman, has a half Basque child, and is generally more voluably racist against the North AFrican and Black migrants to Spain than most, despite being a migrant himself.
It seems to me that people are finding the enemy they want in this. Politicians and 'ordinary' people see the enemy they chose - it seems there is much political capital to be made out of the lives of 200 people.