The public frequently claims that politicians are out of touch. Such charges are sometimes too easily and cheaply made. But not always. Monday was one of the exceptions. Monday's Commons exchanges about the issues raised by the Guardian's revelations about the US government's data mining activities – on which the foreign secretary, William Hague, answered questions for more than an hour – ended with a simple and disturbing conclusion: that most MPs simply do not get it.

For five days, the Guardian's stories, rooted in documents provided by the whistleblower Edward Snowden, have rocked the US political system and echoed around the world. They have done so for one overwhelming reason – because they offer direct and powerful evidence, never seriously denied, about profoundly alarming threats to civil liberty from America's secret state. In them, the National Security Agency stands accused of conducting routine data trawls through US phone, email and social media records without effective scrutiny or proportionate authority. Britain's GCHQ communications eavesdropping headquarters is explicitly stated in the documents to be linked to the Prism operation through which the NSA conducts this work.

Given that the documents are genuine, the facts stated in them must therefore be faced. Tough questions irresistibly follow for British ministers. Were they told? How long has it been going on? Does GCHQ use Prism data on British citizens in the UK? Has the interception commissioner reviewed the system? Has GCHQ submitted evidence about the legality of its work to ministers and oversight bodies? Some of these points were raised by MPs. But Mr Hague took pride in not deigning to answer any of them. To listen to most of the exchanges, you would never have guessed that there is anything whatever to worry about.

Mr Hague, following David Cameron earlier, described an entirely benign and internally consistent world. Here, everything done by Britain's security and intelligence agencies is targeted and lawful. Here GCHQ and the rest are accountable to well-informed ministers and scrutinised by effective parliamentary oversight. So robust and principled is this system, the foreign secretary clearly believes, that he managed to get through the whole Commons session without mentioning Prism by name, without expressing any substantive view about Mr Snowden's revelations, and without saying anything specific about anything in the Guardian's reporting at all.

For Mr Hague to say the concerns are baseless is itself baseless. The reason there was a session in the Commons at all was because the world now appears, because of that reporting, to be a very different place. The reporting raises stubborn issues about the threat to civil liberties. A few MPs guardedly raised questions that challenged the Hague view. His Labour shadow, Douglas Alexander, who managed to mention Prism, asked some "what if?" questions. David Blunkett seemed to query whether Mr Hague's statement covered unsolicited NSA data. The MP for GCHQ, Martin Horwood, was clear that questions about Prism are legitimate. David Davis pointed out that US law was more permissive to state agencies than UK law. And Rory Stewart said that if governments do not explain controversial things better they will feed scepticism about their own assurances. Overall, however, there was a lurching disjunction between what the documents say and what the Commons seemed to want to believe.

One of the British Conservative party's tribal deities, Benjamin Disraeli, famously wrote about two nations, who are "as ignorant of each other's habits, thoughts, and feelings, as if they were dwellers in different zones, or inhabitants of different planets". Monday showed there are two worlds, not just two nations. The gulf between them has yet to be bridged. Yes, national security matters deeply. But so do civil liberties. Mr Hague and the Commons failed badly to get the two into balance. But their duty to do so remains.