Sir, Spanish police warned their French counterparts about the danger posed by Ayoub el-Khazzani when he moved there. French services knew Mr Khazzani was living in France and that he was a threat, yet they didn’t act. Would they have really been more proactive if he had shown his passport at the border in a world without Schengen?

Reintroducing internal passport controls diverts precious resources from targeted, efficient counterterrorism into blanket checks that achieve little other than bothering the good guys and pandering to the far right.

Silvio Sandrone

Triel sur Seine, France

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