A couple of weeks ago, I asked the Scottish National party the following questions: "If independence is achieved, will the Scottish government continue with the extensive surveillance of the civilian population, allowed under the Regulation of Investigatory Powers Act? Is it part of the SNP's programme to break free from this surveillance regime or will an independent Scotland remain a client of GCHQ?"

If I say it myself, this goes to the heart of the independence debate. A sovereign Scotland could not possibly remain integrated in the British systems of surveillance, which include the monitoring of internet searches, texts and emails, and hope to be taken seriously as a new nation state.

The answer from the SNP was fascinatingly dull. "The primary function of government is to ensure the security of its citizens and to protect them, their property and way of life against threats. An independent Scotland will have security arrangements that are proportionate, fit for purpose and reflect a full strategic assessment of Scotland's needs and the threats we may face." The SNP knows full well that a statement on this issue either risks offending those Scots who want their new nation to be free from the British surveillance state or those who believe that the bulk collection of data will protect the country from terrorists. Hence the straight bat.

The SNP is as sly about closing down the discussion on mass collection of data as the coalition government in London. Dr Andrew Neal of Edinburgh University is practically the only person north of Hadrian's Wall thinking intelligently about an independent Scotland's security and surveillance needs. He has organised a series of seminars on national security strategy, its relation to national identity and the ticklish problem of disentangling the spying and communications infrastructures. Just one MSP turned up at the first seminar.

The way this debate has been silenced at both ends of the UK is not just deeply depressing – it is extremely dangerous. For it gives the impression that we don't care about our freedom and that as long as we believe we are safe from terrorists, the government can do what the hell it likes with our information, even if that means building an invincible political power over trade unions, dissenting minorities, legitimate protesters, environmental activists, Her Majesty's opposition... you name it!

In contrast to Britain, the reaction in Germany, France, Spain, Brazil and the United States to the NSA leaks has included protest, vigorous debate and in America the admission from the secretary of state, John Kerry, that the NSA has gone too far and the policy of bulk data collection must be looked at again. Last week's disclosure about Europe-wide surveillance of phone and internet traffic, going on, presumably, without the knowledge of democratically elected assemblies, has caused further outrage. And now Brazil and Germany, angered by the NSA and GCHQ's activities, have drafted a resolution for the UN General Assembly, which declares deep concern about "human rights violations and abuses that may result from the conduct of any surveillance of communications".

This is what democratic response looks like, though you don't see much of it here. In Britain, the government has told us not to worry our silly heads and Labour has remained eloquently silent, because all these problems stem from the casually authoritarian Blair regime, which gave GCHQ the legal powers that are now exposed. Many elements of the media, meanwhile, have suffered some form of moral and intellectual paralysis and accept without question that we should trust the state with the power to access anyone's information.

It seems extraordinary that the Conservative press, so wary of the state in practically every other area, is prepared to trust the intelligence agencies with powers granted under RIPA that are so opaque that they might as well be written in Serbo-Croat. As the Labour MP Tom Watson said of the critical part of RIPA in a Westminster Hall debate on surveillance last week: "Interpreting that section requires the unravelling of a triple-nested inversion of meanings across six cross-referenced subsections linked to a dozen other cross-linked definitions, which are all dependent on a highly ambiguous 'notwithstanding'."

The genius of the law was to mask its own potency, while the genius of the government's response to those concerned about RIPA and its threat to liberty is to dismiss them as extremists and alarmists. The Guardian, which has been lauded all over the world for publishing some of the NSA leaks, is described in the language used for a "treasonous" insurgency, and the prime minister has even murmured threats against the newspaper.

The truth is that opposition to these laws is in fact no more than a politically moderate concern for liberty and democracy. That is all. The debate does occasionally fire up, as in the Westminster Hall event last week, when there were some terrific contributions from its Lib Dem sponsor, Julian Huppert, the Labour MPs Tom Watson, John McDonnell and David Winnick, and the staunch Tory, Dominic Raab. But this was just a debate – RIPA was not being redrafted; no action will be taken to increase oversight of the intelligence agencies; and almost no one heard the arguments, because most papers and TV didn't cover it.

This week, we may expect a further push against open and frank discussion when the heads of the three intelligence agencies appear in front of the Commons oversight committee on TV. That might seem reassuring but let us hope the occasion won't be an attack on those of us who are legitimately concerned about the law and indeed the level of meaningful oversight by parliament.

Happily, these won't be the only voices heard. A meeting, called by me and two friends to support the responsible publication of the NSA leaks by the Guardian and to urge a proper national debate, takes place at the Royal Institute of British Architects in London tomorrow. There will be speakers from all the main parties, NGOs and journalism, including Wolfgang Büchner, editor-in-chief of Der Spiegel, which published revelations about the NSA bugging Angela Merkel's phone.

We have received support from a wide range of public figures, including the public law and human rights lawyers Lord Pannick QC, Helena Kennedy QC, Philippe Sands QC, Philip Pullman and John le Carré, Jimmy Wales of Wikipedia, Brian Eno, David Gilmour and Neil Tennant, and the directors Peter Kosminsky and Stephen Frears.

The debate cannot be silenced, north or south of the border.

'Mass surveillance, the debate must not be silenced' is at RIBA, London W1, 6.45pm tomorrow. For tickets email surveillanceevent@gmail.com