SCOTLAND puts the great into Great Britain, Philip Hammond, the Defence Secretary, will declare today as he insists the bond that binds the four nations of the Union is "precious".
Mr Hammond will tell workers at Thales Optronics in Glasgow that nowhere is this best exemplified than in the brave members of Britain's armed forces.
He will say: "Drawn from the four corners of these islands, nothing epitomises more the strength we derive from being a United Kingdom than the men and women in our navy, army and air force, coming together with a common purpose to keep our country and our people safe and secure."
His words follow a parallel push on defence matters from the Better Together campaign.
Alistair Darling, its leader, on a visit yesterday to another defence firm in Glasgow accompanied by Labour colleague Vernon Coaker, the Shadow Defence Secretary, highlighted how many thousands of jobs relied on the UK's defence industry. "It's a great success story and has kept generations of families in work for many years. Leaving the UK would put that at risk."
Ian Walker, managing director of Glasgow-based Walker Precision Engineering, which makes parts for submarines and tanks, echoed the point, saying independence would mean "dreadful uncertainty" for his firm's contracts and jobs.
Describing himself as a "proud and whole-hearted believer in the success of our unique partnership of peoples", in his speech Mr Hammond will make reference to the centenary of the start of the First World War.
He will say: "This year, of all years, is a time to remember and to commemorate the millions of men from all parts of the United Kingdom who stood together in the trenches in France and Belgium, many of whom never returned, but who, together - English, Scots, Irish and Welsh - protected our freedom and our way life."
Defence matters in this debate, he will argue, not just because of Britain's proud history of joint endeavour but also because it provides the security and peace of mind that underpins almost every single other area of the constitutional debate.
Insisting the bonds that exist between the different parts of the UK are "precious", the Secretary of State will say: "It is our shared history, our common values and our unity of purpose which makes us what we are today. It is Scotland which makes the UK united and adds the Great to Great Britain."
Mr Hammond will also accuse Alex Salmond of resting his entire economic policy on "trying to dictate to the rest of the UK that Scotland could keep the pound, when the UK Government has already made it absolutely clear it's not an item up for negotiation. A currency union without fiscal and political union simply doesn't work; the only way to keep the UK pound is to keep the UK together".
The Defence Secretary will go on to say the First Minister also wants to "dictate the timescales" for removing the UK's nuclear deterrent by 2021 but stresses, if there were a Yes vote, talks about costs and timescales would be long and protracted. "Any notion it would be quick and easy is just plain wrong," he will add.
Mr Hammond's speech comes as Britain's military top brass have come together to warn that any attempt to remove Trident from the Clyde would cost billions of pounds and cast a "dark shadow" over an independent Scotland's international reputation.
Admiral Sir Mark Stanhope, former first sea lord and chief of naval staff, has sent a letter to First Minister Alex Salmond co-signed by former heads of the army, navy, air force and intelligence warning the SNP's proposed constitutional ban on nuclear weapons "would be unacceptable for Nato".
Scotland would be "a new small nation in an uncertain world" in need of allies, but Nato "could hardly be expected to welcome a new member state whose government put in jeopardy the continued operation of the UK independent nuclear deterrent", Sir Mark said.