What do Alex Salmond and Nigel Farage have in common? Answer: they both believe that by walking away from a family of nations working together they become stronger and more independent. The attitudes and language of both men in this respect are remarkably similar. Yet the evidence that a country becomes more independent in the modern world when it breaks away from a group like the EU or UK is very slender. Norway and Switzerland are often, rightly, cited as examples of how dependent both countries are on a successful EU and how much they have to tailor their policies to fit in with, or follow their larger neighbour. True independence it is not.

For Scotland the same would be true. The policies of the rest of the UK would largely determine what Scotland could or could not do – whether they have to rely on the British pound and fiscal and monetary policies as decided in London, or whether they have to pay for the benefit of piggy-backing onto a range of UK services such as consular and diplomatic services overseas.

Trade negotiations will remain a crucially important role of the EU, and as long as the UK remains a member we will have a major say in what EU policies are. Scotland out of the UK and not a member of the EU would have no say, and even if you take the wildly optimistic view that Scotland will be able to join the EU, re-entry would take years. And on what terms? An independent Scotland is far more likely to face long and complex negotiations and a possible veto by other member countries worried about break away regions within their own borders.

Joining the Euro will be a must, so bang goes the relationship with the British pound and up comes the interesting question of border and financial controls. This is neither a clever policy, nor is it a policy leading to real independence, which is a far weaker concept in the modern world than it used to be. Both the EU and the UK were formed in part as a means to ending endemic conflicts. The 1707 Act of Union brought to a halt the internecine conflicts across the border. The EU aims to do much the same and it seems to be succeeding rather well.

Curiously, the Act of Union had the basic elements of a federal system before modern federalism was invented. Scotland and England have different legal systems, and church and government relationships are different in Scotland, Wales and England. This knowledge should lead us naturally to the idea of the UK developing a truly federal system designed for the modern world. Many people have been arguing this case for some years now and breaking up the family of nations that is the UK is a serious distraction from that goal.

Both Farage and Salmond should also take into account the effect on their neighbours of the announcement that they want to leave the family. As a young British teenager travelling in Europe in the immediate post-war years, I thought I had won the world popularity stakes! We were admired everywhere for our stand during the war and for creating so many of the post-war institutions and constitutions that have given us such stability today. Now look at our popularity. We have alienated many of our former admirers to the extent that many continental people are saying “good riddance if they go”.

Whether you believe in staying in the EU or leaving it, the worst of all possible worlds is to poke your friends in the eye – it doesn’t lead to generous settlement of leaving terms. The same applies to Scotland. Just as there are some Scots who harbour a strong dislike of the English, there are also some English who dislike the Scots. Nationalism divides and causes bitterness, which is why it is naïve for Salmond to believe that the rest of the UK will accept Scotland walking out of the family, taking their share of the wealth, but then knocking on the door the next day and saying they want to use the pound and have a say on managing the finances – this is not going to make for a happy separation.

The absurdity of the Farage/Salmond approach is that none of us lose our central national characteristics or cultures by merging economic and political powers. The UK has been, by any standard, a remarkably successful union, creating peace and prosperity while retaining cultural differences. The same can, and in my view will, be true of Europe.

Both Farage and Salmond need to take a long, hard look at the modern world and recognise that independence can be in name only. The modern world is more integrated and frankly a far better place for this. The reason why Salmond is not gaining the support of the younger generation in the way he hoped is because they are not excited by borders, whether as lines on a map or lines through the hearts and minds of real people. Salmond and Farage are part of a generation brought up on the importance of borders. Their time has passed. The modern world has better things to do than squabble over borders.

Lord Soley of Hammersmith is a Labour peer