§ Mr. Bestasked the Secretary of State for Defence if he will estimate the cost and the number of submarines and cruise missiles which would be necessary to equal the capacity of the Trident missile system by way of submarine-launched cruise missiles; whether such a system is of equal deterrence value; and if he will make a statement.
§ Mr. ButlerI refer my hon. Friend to the very full statement on this subject by my right hon. Friend the Minister of State for the Armed Forces on 29 November 1984, at columns 1125–28. The Government considered cruise missile options before decisions on Trident were taken and concluded that they were far less cost effective. This conclusion remains unchanged. Many more cruise missiles and warheads would be needed to provide a deterrent equivalent to that of a ballistic missile force, and at least twice the number of submarines would be necessary. Such a force would be considerably more expensive to procure and run than our planned Trident II force and would have a much inferior capability against any future developments in Soviet defensive systems.