We all remember President Obama's smiling face, full of hope and trust, in his first campaign: "Yes, we can!" – we can get rid of the cynicism of the Bush era and bring justice and welfare to the American people. Now that the US continues its covert operations and expands its intelligence network, spying even on its allies, we can imagine protesters shouting at Obama: "How can you use drones for killing? How can you spy even on our allies?" Obama murmurs with a mockingly evil smile: "Yes, we can."

But simple personalisation misses the point: the threat to freedom disclosed by whistleblowers has deeper, systemic roots. Edward Snowden should be defended not only because his acts annoyed and embarrassed US secret services; what he revealed is something that not only the US but also all great (and not so great) powers – from China to Russia, Germany to Israel – are doing (to the extent they are technologically able to do it).

His acts provided a factual foundation to our suspicions of being monitored and controlled – their lesson is global, reaching far beyond the standard US-bashing. We didn't really learn from Snowden (or Manning) anything we didn't already presume to be true. But it is one thing to know it in general, another to get concrete data. It is a little like knowing that one's sexual partner is playing around – one can accept the abstract knowledge, but pain arises when one gets the steamy details, pictures of what they were doing …

Back in 1843, the young Karl Marx claimed that the German ancien regime "only imagines that it believes in itself and demands that the world should imagine the same thing". In such a situation, to put shame on those in power becomes a weapon. Or, as Marx goes on: "The actual pressure must be made more pressing by adding to it consciousness of pressure, the shame must be made more shameful by publicising it."

This, exactly, is our situation today: we are facing the shameless cynicism of the representatives of the existing global order, who only imagine that they believe in their ideas of democracy, human rights etc. What happens in WikiLeaks disclosures is that the shame – theirs, and ours for tolerating such power over us – is made more shameful by publicising it. What we should be ashamed of is the worldwide process of the gradual narrowing of the space for what Kant called the "public use of reason".

In his classic text, What Is Enlightenment?, Kant contrasts "public" and "private" use of reason – "private" is for Kant the communal-institutional order in which we dwell (our state, our nation …), while "public" is the transnational universality of the exercise of one's reason: "The public use of one's reason must always be free, and it alone can bring about enlightenment among men. The private use of one's reason, on the other hand, may often be very narrowly restricted without particularly hindering the progress of enlightenment. By public use of one's reason I understand the use that a person makes of it as a scholar before the reading public. Private use I call that which one may make of it in a particular civil post or office which is entrusted to him."

We see where Kant parts with our liberal common sense: the domain of state is "private" constrained by particular interests, while individuals reflecting on general issues use reason in a "public" way. This Kantian distinction is especially pertinent with internet and other new media torn between their free "public use" and their growing "private" control. In our era of cloud computing, we no longer need strong individual computers: software and information are provided on demand; users can access web-based tools or applications through browsers.

This wonderful new world is, however, only one side of the story. Users are accessing programs and software files that are kept far away in climate-controlled rooms with thousands of computers – or, to quote a propaganda-text on cloud computing: "Details are abstracted from consumers, who no longer have need for expertise in, or control over, the technology infrastructure 'in the cloud' that supports them."

Here are two telltale words: abstraction and control. To manage a cloud there needs to be a monitoring system that controls its functioning, and this system is by definition hidden from users. The more the small item (smartphone) I hold in my hand is personalised, easy to use, "transparent" in its functioning, the more the entire setup has to rely on the work being done elsewhere, in a vast circuit of machines that co-ordinate the user's experience. The more our experience is non-alienated, spontaneous, transparent, the more it is regulated by the invisible network controlled by state agencies and large private companies that follow their secret agendas.

Once we choose to follow the path of state secrets, we sooner or later reach the fateful point at which the legal regulations prescribing what is secret become secret. Kant formulated the basic axiom of the public law: "All actions relating to the right of other men are unjust if their maxim is not consistent with publicity." A secret law, a law unknown to its subjects, legitimises the arbitrary despotism of those who exercise it, as indicated in the title of a recent report on China: "Even what's secret is a secret in China." Troublesome intellectuals who report on political oppression, ecological catastrophes, rural poverty etc, got years in prison for betraying a state secret, and the catch was that many of the laws and regulations that made up the state-secret regime were themselves classified, making it difficult for individuals to know how and when they are in violation.

What makes the all-encompassing control of our lives so dangerous is not that we lose our privacy, that all our intimate secrets are exposed to Big Brother. There is no state agency able to exert such control – not because they don't know enough, but because they know too much. The sheer size of data is too large, and in spite of all intricate programs for detecting suspicious messages, computers that register billions of data are too stupid to interpret and evaluate them properly, ridiculous mistakes where innocent bystanders are listed as potential terrorists occur necessarily – and this makes state control of communications even more dangerous. Without knowing why, without doing anything illegal, we can all be listed as potential terrorists. Recall the legendary answer of a Hearst newspaper editor to Hearst's inquiry as to why he doesn't want to take a long-deserved holiday: "I am afraid that if I go, there will be chaos, everything will fall apart – but I am even more afraid to discover that if I go, things will just go on as normal without me, a proof that I am not really needed!" Something similar can be said about the state control of our communications: we should fear that we have no secrets, that secret state agencies know everything, but we should fear even more that they fail in this endeavour.

This is why whistleblowers play a crucial role in keeping the "public reason" alive. Assange, Manning, Snowden, these are our new heroes, exemplary cases of the new ethics that befits our era of digitalised control. They are no longer just whistleblowers who denounce the illegal practices of private companies to the public authorities; they denounce these public authorities themselves when they engage in "private use of reason".

We need Mannings and Snowdens in China, in Russia, everywhere. There are states much more oppressive than the US – just imagine what would have happened to someone like Manning in a Russian or Chinese court (in all probability no public trial). However, one should not exaggerate the softness of the US: true, the US doesn't treat prisoners as brutally as China or Russia – because of its technological priority, it simply does not need the brutal approach (which it is more than ready to apply when needed). In this sense, the US is even more dangerous than China insofar as its measures of control are not perceived as such, while Chinese brutality is openly displayed.

It is therefore not enough to play one state against the other (like Snowden, who used Russia against the US): we need a new international network to organise the protection of whistleblowers and the dissemination of their message. Whistleblowers are our heroes because they prove that if those in power can do it, we can also do it.