Daily Telegraph – 10 February 2014

We do not believe that the Royal United Services Institute (RUSI) has, as an organisation, endorsed the idea that continuous at-sea deterrence can safely be abandoned by our Trident nuclear force. The views expressed in the RUSI analyst Hugh Chalmers’ convoluted paper (report, January 31) are clearly labelled as “entirely the author’s own” and should not be ascribed to the institute as a whole.

His conclusion that

“even an inactive fleet of submarines can help to deter actors from seriously threatening the UK”

is based on a fallacy. Though admitting that such a fleet

“would be vulnerable to a no-notice [enemy] strike”,

Mr Chalmers asserts that

“such an attack seems highly unlikely without prior indication or provocation”.

If we were known to have a part-time deterrent posture, any rational enemy would have maximum incentive to strike without warning, precisely to prevent the reconstitution of our power to retaliate. History abounds with cases of aggression which took the victim wholly by surprise. It also teaches us that some aggressors may take enormous risks if, but only if, they think they may avoid the consequences.

It is the certainty of retaliation, as much as the magnitude of retaliation, which lies at the heart of deterrence. An uncertain deterrent may ward off some attackers, but it would be an open invitation to others that the risks are now worth taking.

JULIAN LEWIS MP
BERNARD JENKIN MP
House of Commons
London SW1A 0AA