The columnist has written an interesting column.

I disagree with her, though. 

She seems to place blame at police, for not doing  a very good job at policing, such as where she complains that one suspect "was flagged to the authorities at least five times as an individual who was showing signs of radicalization" and "the same pattern (of police shortcomings) is being repeated... following the London attack, with reports that locals contacted the police two years ago to report the individual believed to be the terrorist ring leader."

I mean, she is free to make that argument, to blame police shortcomings.

But security experts tell us, compellingly, that the police thus have to be correct one hundred percent of the time over and over (an impossibility) whereas an individual attacker only needs to pull it off once.

Look, if you are going to shift this so much on police, expecting more arrests and spying ahead of time, then expect erroneous arrests and less freedom, too. Not ideal!