Trevor Royle rightly draws attention to the fact that Nato's nuclear capacity is not just in the US, UK and France but that there are air-launched nuclear weapons based in five other countries ("Joining Nato will embroil Scotland in nuclear dialogue", The Herald, July 21).

There was significant pressure, particularly in Germany, to have these removed but the recent Nato Deterrence and Defence Posture Review decided to upgrade them. Former Labour Defence Secretary Des Browne, in a speech in the House of Lords, warned that Nato was creating conditions for "sleepwalking back into the Cold War". He attacked the lack of progress towards disarmament and stated that "all tactical weapons in Europe not only pose a risk to this continent's safety and security, they lack any credibility to deter 21st-century threats".

Angus Robertson wants the SNP to sign up to this while continuing to claim he supports a non-nuclear defence policy. In the process he seems prepared to abandon a clear and principled position which has given the SNP a strong profile and significant support for an ambivalent mess that will be constantly open to attack.

Isobel Lindsay, 9 Knocklea Place, Biggar.