The crucial thing about the latest revelations from the secret documents leaked by the whistleblower Edward Snowden is their scope. When the Guardian first began publishing Mr Snowden's documents seven months ago, it was immediately apparent that they described secret data-trawling operations by America's NSA and Britain's GCHQ of almost limitless reach. One of the earliest official responses to such claims was that they were simply alarmist. Yes, some officials may have privately conceded, the documents described systems with the theoretical potential to reach deep into everyday civic life and personal communications. But in practice, they insisted, the only people who needed to be worried were terrorists. Haystacks had been built, as the officials put it, but it was the needles within them that mattered. The rest of us could sleep safe, since the watchers were only interested in those who were plotting to do us all harm.

That seemed a dangerously complacent view even then. But it is a wholly discredited argument now that more details have been made public. The latest documents reveal more than 1,000 targets of British and American surveillance of whom very few can seriously be seen as threats of that sort. On the contrary, though the targets include some Israeli, Taliban and Chinese activities, they also include the EU's competition commissioner, who is hardly a threat to this country. Others on the snoopers' hitlist are German government buildings in Berlin, embassies in Africa, and German communications with Turkey and Georgia – revelations likely to cause a fresh storm in Berlin. Elsewhere the target list includes a French diplomat, the oil giant Total, and the French-owned defence group Thales. The United Nations development programme, now headed by the former New Zealand prime minister Helen Clark, is there too, along with the Unicef children's charity and the UN's institute for disarmament research, the French-based NGO Médecins du Monde, and the head of the economic union of West African states.

These are not, in the main, targets who are plotting to do us all harm. They are foreign governments, NGOs, international bodies and sometimes named individuals. Many of them are allies pursuing objectives and activities that the US and UK governments actively support. There is no way that the attention to these targets can be explained by terror threats. Indeed, there is no obvious explanation of some of their presence on the NSA-GCHQ surveillance list, save one – that the snoopers have the capacity to keep them under surveillance and therefore do so. We are spying not because we need to or should but because we can.

This week, the review board appointed by President Obama to examine the NSA's data mining activities came up with 46 detailed proposals for reform, including the need for restrictions on the scope of NSA activity as well as stronger legislative and legal oversight over its programmes. Mr Obama responded that he was "open to many" of the reforms set out in the report. On Friday he promised changes to international surveillance and "a pretty definitive statement in January." All this is a direct engagement with Mr Snowden's revelations. It is the right course.

Britain should match the American response. Ministers need to take the revelations much more seriously than they have done. The latest documents make the need more urgent than ever. They show UK surveillance of close allies, including France and Germany, and UN bodies. Such actions directly damage Britain's standing in the wider world. Simply to refer such issues to the Westminster intelligence and security committee, which has neither the credibility nor the resources to assess them objectively or adequately, is irresponsible. Major rethinking and repair work are essential. The government must commission a panel of independent experts on the American model without delay.