With the latest opinion poll indicating a slight lead for the Yes camp, the referendum on Scottish independence on 18 September will be close. It looks like there will be a big voter turnout.

Nonetheless, it took the intervention of Tony Abbott to make this big news in Australia, making it clear that Scotland was part not only of the United Kingdom, but of team Australia.

“I think that the people who would like to see the break-up of the United Kingdom are not the friends of justice, the friends of freedom, and the countries that would cheer at the prospect … are not the countries whose company one would like to keep.”

It is hard not to be reminded of Macbeth (or “the Scottish play”, as it is known in theatre circles): “A poor player/That struts and frets his hour upon the stage/And then is heard no more. It is a tale/Told by an idiot, full of sound and fury/Signifying nothing.”

But now, less than two weeks before the poll, British prime minister David Cameron has finally got Abbott’s message, suggesting that “in that dangerous world and insecure world of terrorist threats and other threats, isn’t it better to be part of the United Kingdom?”

Why? Because the UK “has a top five defence budget … has some of the best security and intelligence services anywhere in the world … is part of every single alliance that really matters in the world in terms of NATO, the G8, the G20, European Union, a permanent member of the Security Council of the UN”.

Despite what Abbott and Cameron might think, all of these are pretty compelling reasons to get out.

Another reason is the unholy alliance of Tories, Labour and Lib-Dems who oppose independence – all the parties that have overseen austerity for decades. The anti-independence Better Together campaign is backed by every major media outlet in Scotland as well as London.

The No case has focused on reactionary notions of British nationalism. The opponents of independence have also relied on fear-mongering about the viability of an independent Scotland, as a way to deflect attention from the real issues that face workers on both sides of the border. Forget about the uncertainty that workers of all nationalities face every day under capitalism: it’s the uncertainty of business prosperity that matters.

Socialists should support the break-up of the United Kingdom. There’s nothing for the working class in maintaining its military and diplomatic coherence. The main enemy is British capitalism and imperialism, the British nationalism that justifies them and the British state that upholds them. To weaken them in any way is a step forward, even if small.

On the other hand, a No vote will strengthen the British state and all it represents. With the Tories in Westminster already in disarray, a Yes vote can help to destabilise the ruling class further. It can open a space for expectations of something better.

Much of the Yes campaign has focused on anti-austerity and anti-privatisation arguments – that breaking from the United Kingdom should mean breaking from poverty, cuts to welfare and the billions wasted on Trident nuclear submarines (currently sited in Scotland).

None of this is a question of national liberation. Scotland is not an oppressed nation within the United Kingdom. It was a partner and beneficiary from the British Empire and subsequent imperialism. An independent Scotland would not be anything other than another capitalist nation.

The force likely to benefit electorally from a vote for independence is the pro-capitalist Scottish National Party. The SNP wants to maintain the monarchy and stay in NATO. SNP leader Alex Salmond was previously an economist at the Royal Bank of Scotland. His role as Scotland’s current first minister has been to preside over austerity measures.

So workers’ raised expectations if the Yes vote succeeds will be on a collision course with the SNP.

Workers need unity in struggle against the bosses. That does not depend on the unity or otherwise of the United Kingdom. There are obstacles to that unity but they are the low level of struggle, the cowardice and politics of trade union officials and all the old divide and rule tactics such as racism. Changing the location of parliament from Westminster to Edinburgh will not bring real change. Only workers’ own struggles can do that.