Would a British nuclear Tomahawk improve deterrence?

Should Britain develop its own nuclear warhead for Tomahawk?

A British nuclear Tomahawk is favoured as a supplement to the ballistic-missile deterrent, with a warning that its lower apparent cost could encourage pressure to replace that deterrent.

A recalled conversation with a naval officer raises a budget concern about putting nuclear weapons on attack submarines. Once those submarines carried nuclear Tomahawks, accountants could present them as a cheaper substitute for the dedicated ballistic-missile deterrent. The discussion considers cruise missiles and air-launched weapons as additional options where that substitution would not follow. Its objection concerns procurement decisions based on the cheapest apparent deterrent. The later clarification identifies the question as whether Britain should build its own warhead for Tomahawk.