• BOB Davenport’s May 18 letter (Unclear option) about the cyber attack on the National Health Service and Trident, our nuclear defence system, brought dark humour to a serious issue.

The potential hijack of nuclear weapons was flagged as a concern by the director of Algorithm: The Hacker Movie in interviews. It is free to watch online now, and it shows how a hack into the Trident control system (which is incidentally Windows XP-based) could be very costly indeed.

We are safer without it and instead investing those billions directly into saving lives in the NHS, and in security against cyber terrorism.

B JANE
Chenies Street Chambers
WC1