What has become known is that America’s National Security Agency last week intercepted electronic communications (probably conversations on satellite telephones) between Ayman al-Zawahiri (pictured, left), Osama bin Laden’s successor as head of al-Qaeda, and Nasser al-Wuhayshi (pictured, right), the leader of the international terrorist group’s Yemen-based affiliate, al-Qaeda in the Arabian Peninsula (AQAP), and Mr Zawahiri’s chosen deputy. In recent years, as al-Qaeda’s central leadership based in North Waziristan has suffered unrelenting attrition from American drone strikes, AQAP has been the most active branch of the network in plotting attacks on targets in the West. According to those who have been briefed on what passed between the two men, Mr Zawahiri had ordered an attack or series of attacks on the Sunday before the ending of Ramadan on August 7th, which would have ranked as among the most deadly since 9/11.

It is also not yet apparent why the White House opted to make such a dramatic public statement of its concerns rather than use the information to disrupt the plot. Not only is there a significant economic cost from the consequent delays to travel, but according to intelligence sources there are potentially major security drawbacks as well. First, al-Qaeda has been given precious information about American surveillance capabilities that will help it keep its communications more secure in future. Secondly, the plotters might have a “plan B” up their sleeves that the intelligence agencies have as yet no knowledge of. Thirdly, it goes strongly counter to the administration’s previous claims that, thanks to its efforts, al-Qaeda's ability to carry out complex operations against Western targets had declined to such an extent that it was on the brink of strategic defeat.

There is little doubt that what influenced Mr Obama and his advisers to act as they did was the tragic death of Ambassador Christopher Stevens and three others when the American consulate in Benghazi came under violent siege by jihadist fighters, possibly linked to al-Qaeda, on September 11th 2012. Eighteen hours before the assault on the consulate, Mr Zawahiri had issued a video demanding attacks on Americans in Libya to mark the anniversary of 9/11. In its aftermath, Republican critics accused the administration of providing a misleading account of what had taken place in order to absolve itself of being complacent about the threat and tardy in its response. Even if the shriller claims were not borne out by the subsequent investigation, a good deal of mud stuck at a time when Mr Obama was trumpeting his national-security credentials ahead of last November’s election.

However, on this occasion, normally hostile congressional Republicans, such as New York’s Pete King and Saxby Chambliss, the ranking member of the Senate Intelligence Committee from Georgia, were quick to praise the NSA (recently under some pressure after the revelations of Edward Snowden about the extent of its data gathering both at home and abroad) for its work and to support the administration’s reaction. On August 5th it was reported from Yemen that four al-Qaeda suspects, who may have been connected to the plot, had been killed by an American drone strike.

But while the White House may be congratulating itself on its short-term handling of the crisis, longer-term questions will have to be addressed. The first of these is the beefing up of security arrangements at diplomatic missions in dangerous places, one of the post-Benghazi recommendations that have yet to be implemented. The second is whether there needs to be a thorough reassessment of the threat that continues to be posed by al-Qaeda and its extensive network of affiliates and jihadist fellow travellers.

Although that threat, at least as far as the West is concerned, has appeared to wane in recent years and the “Arab spring” for a time caught it off balance, al-Qaeda has proved itself to be both resilient and adaptable. In Yemen, AQAP, in cahoots with local tribes, controls a significant amount of territory and is at a communications and fund-raising nexus for the rest of the organisation. In Syria, Jabhat al-Nusra, by far the most powerful of the rebel militias, has been absorbed by al-Qaeda in Iraq, which itself has re-energised the bloody Sunni insurgency against the Shia-dominated government of Nuri al-Maliki. Al-Qaeda is increasingly active in the open spaces of Sinai and sees opportunity in the ousting of the Muslim Brotherhood government in Cairo. The departure of NATO combat forces from Afghanistan by the end of next year may allow it to return to some parts of the south and east of the country under Taliban protection, while the leadership in Pakistan’s tribal badlands may also be anticipating a slackening in the drone campaign that has thinned its ranks.

Mr Obama recently talked about the “war on terror” coming to an end. It is true that most of al-Qaeda’s focus is currently on local struggles rather than the “far” enemy in the West. But compared with 12 years ago, it has many more fighters and holds much more territory. Its priorities could easily shift. If a conversation between Mr Zawahiri and Mr Wuhayshi can be the cause of so much disruption, Mr Obama may have to think again.