their was talk a couple of years back that the proposed new type 26 frigates might be built in S Korea at the Daewoo shipyard ...
Nope- there's a commitment to retaining major surface combatant construction in the UK and there's a terms of business agreement written around that to provide BAE with a steady stream of work. If Scotland ceased to be a part of the UK, they're not getting military construction work *unless* it got tendered out internationally. That would have to be on a competitive basis. Scotland would be unlikely to be capable of putting together a bid that could stand alongside DCNS, Fincantieri or Daewoo.
In terms of Trident, irrespective of the parties leading the "Yes" vote campaign, they don't have a majority - there are more folk in England in favour of Scottish independence than there are in Scotland. You run the figures across the Scottish population and they've been broadly in support of Trident as have the rest of the population of the UK - every survey over the last twenty years has plumped more or less in the same direction, that a bit more than half the population tends to be in favour of an independent nuclear deterrent. You can dig out the odd poll commissioned by some left leaning organisation or another where the phrasing of the questions has skewed that number down a bit but fairly consistently the support is there for Trident.
In short, a vote for independence is not a vote of confidence in the SNP, nor is it whole hearted support for all their policies.
I've seem some spectacularly biased comments from the various Scots nationalists about the English littering Scotland with nuclear submarines, which completely ignores the fact that the entire Polaris fleet is laid up in England awaiting disposal. Ditto comments on leaving all our dangerous nuclear weapons up there when in fact there are many more warheads in England.
Scotland has also seen some tremendous benefits from Trident - the Coulport Arsenal and special munitions jetty was the second biggest engineering project in Britain in the 1990's - second only to the Channel Tunnel. Faslane is one of the larger employers in the area. It's interesting that one of the first results of the announcement regarding a vote for independence was the mayor of a town in Wales offering to host Trident...
Post independence Scotland would have an awkward and imperfect balance of high end platforms with a stack of low end ambitions, little in the way of logistic train that could help support Scots forces operate at distance and little to promise it's members in terms of career progress.
And yes, there would be barbed wire going up along the border - because for the first time since the Union of the two countries, England would be on the border of a foreign country to which it would have to close it's borders. Scotland won't automatically inherit the UK's exception to the Schengen Treaty, meaning that every job mobile Rumanian or what have you will travel to Scotland and then to England via the border unless we institute checks...
Or, of course, Scotland does blossom to become the socialist workers paradise the SNP promise, in which case, they'll all stay that side of the border. Best of luck...
And I speak as someone with Scots blood on both sides of the family