Should the SNP "expel Trident from the Faslane base as quickly as they can" then what would remain of UK after a secession would be too small to afford some significant defence of any sort, would it be an Air Force, an Army, a Navy or a nuclear "triad" - which for the moment is a one-finger element, with US warheads and US control in any case.
So in other words UK would become smaller, and the significant foreign population with no real british interests or feelings would become more apparent in perspective (just watch the number of indians who discover themselves scottish, as a result of some resentment towards "colonial" England...)
How sad that a country which didn't surrender in WWII and led the fight of the Free World for two years alone (75 years ago, anyway - it was a different generation) has now become so much prone to self-disbanding and desintegration ?
Being from another european country which still has independant nuc' submarines and bombers, along with MPA and aircraft carriers, I cannot prevent myself from thinking that we - and others - should benefit from that semi-retirement of this island country from the international scene, as a result of its reduction in size...
It seems the US got the same conclusion.